Show notes and related resources

Henry Louie: Personal page with links to textbook and teaching resources

Textbook, 'Off-Grid Electrical Systems for Developing Countries': available free for download by Springer until end of June

KiloWatts for Humanity: not-for-profit organisation website

Podcast Summary

We discuss the technical considerations of off-grid electrical systems, common pitfalls or misunderstandings in practical applications, his work with non-for-profit organisation 'KiloWatts for Humanity' and the importance of considering the potential negative impacts of well-meaning efforts.

Show notes

• (1:30) Henry Louie's background, how he started working in the off-grid energy industry

• (6:00) Background to the textbook: intended audience, why he wrote the textbook, and the need for a single textbook to pull together the key technologies and concepts for off-grid energy sector

• (11:00) Typical sources of training for people working in the sector

• (14:30) Other types of training events that Henry Louie has provided, and what he typically covers

• (16:40) Factors to consider when selecting the generation source for off-grid systems (considering wind, diesel, solar etc.)

• (22:50) Common misconceptions or misunderstandings encountered in the sector (over-engineering systems, over-reliance on surveys to estimate electricity load)

• (29:20) His work with Kilowatts for Humanity (KWH); reasons they separated the non-profit from the university and the importance of ensuring long-term commitment to off-grid energy projects; the importance of using local installers; how to ensure sustainability of off-grid systems

• (37:50) Quick introductions to some electrical concepts:

  • AC-DC coupling

  • Load factor

  • Grid tied inverters

  • Bypass diodes

• (41:40) Process of writing the textbook

• (44:50) Other considerations for off-grid energy systems, e.g. use of donated equipment, ensuring the use of local installer companies and the need for capacity building, the potential unintended consequences of good intentions.

• (52:40) The choice of 'developing countries' for the title of his textbook

• (55:30) How to access a copy of the textbook

• (56:20) Where the name KWH came from

• (57:15) Recommended books: Out of Poverty by Paul Polak; The Impact of Electricity: Development, Desires and Dilemmas by Tanja Winter

• (59:15) Hopes for the off-grid sector in the next 5 years: the need to talk about e-waste; the ethics of switching off systems when payments are delayed.

Interview Transcript

Transcribed by Felipe Rivera-Uribe

Distributing Solar: Henry, welcome to Distributing Solar. It's great to have you here. You're a professor in the Department of Electrical and Computer Engineering at Seattle University and have a bachelor's, master's, and a PhD in electrical engineering. You've been working in the energy access sector since 2008, co-founded the nonprofit Kilowatts for Humanity in 2015, and in 2018 published a textbook: Off-Grid Electrical Systems in Developing Countries. Could you perhaps start by telling us why you decided to focus on electrical engineering and then also how you got interested in developing countries?

Henry: I'm currently a professor at Seattle University and I specialize in the area of electric power engineering. Before coming to Seattle University, I hadn't been involved in off-grid solar at all and quite frankly, I was unaware that so many people struggle with electricity access, but that’s not to say that I didn't see the connection between electricity access and prosperity. I saw that pretty early on.

I got started in the power engineering industry at a fairly young age. I was actually 17 years old when I started working as a field technician for a company and I commissioned power plants, mostly natural gas and coal fired power plants and some geothermal. I did this while I was going to school to earn my bachelor’s degree. So, this hands-on approach that I had starting from a young age really got me involved in electrical engineering. Even back then I remember seeing and being around these massive generators and these huge power transformers and hearing them humming and the crackle of a 5,000 Volt power line and I could just feel the energy. I think I just saw that connected between the power I was helping produce and the modern society that we live in.

After finishing graduate school, I worked for a renewable energy startup company here in Seattle, where I worked on wind energy forecasting. And then in 2008 I started at Seattle University. You have to understand that Seattle University is a Jesuit university and my department really focuses on undergraduate academics. Being a Jesuit university, the faculty are encouraged to pursue activities at the intersection of our expertise and humanity. And so, when I started at Seattle University, I wasn’t exactly sure what that meant. I had come from the large-scale utility world, everything I had touched had been MegaWatts in size and a little bit in the background of people’s mind. I didn’t see a research angle or what I could do to really impact the world’s most vulnerable.

The person that introduced me to this concept of humanitarian engineering and energy poverty is a Jesuit priest named Father Bert Otten. Father Bert Otten is just an incredible individual. He's a priest and he also has a PhD in electrical engineering. He taught at Seattle University for a number of years, but we never overlapped there. He now lives in Zambia - he's been there for quite some time now - and he's been doing what I would call appropriate technology projects for decades. I had the opportunity to spend some time with him in Zambia and through that seeing firsthand the challenges that energy poverty brings, I mean, it really clicked. I thought this is a way that I could take my background in power engineering and apply it in a way that really helps the world's most underserved people.

So I started working on what I would call novelty student projects with Father Otten and some students at my university like developing hand-cranked generators to charge cellphones from scavenged materials and that sort of thing. But over time, each project that we did was larger and more complex, and these weren’t novelty projects but actual projects that began to impact people’s lives. We started using wind turbines and solar. I found myself more immersed in the industry and started working with groups like IEEE Smart Village and started publishing a lot. I even spent a year living in Zambia as a Fulbright Scholar where I looked at electricity access issues. Eventually we were doing so many projects that we spun off our efforts as a non-profit organization called KiloWatts for Humanity. So that’s how I got involved and it’s just been an amazing experience so far.

Distributing Solar: Great. I'd love to discuss a bit about your textbook, which you've called Off-Grid Electrical Systems in Developing Countries. Why did you decide to write the book and who is your intended audience?

Henry: I think I wrote the book for three reasons.

First, I felt a book like that really needed to be written. If you look around, you'll find a few books on electricity access, but some subset of those are going to actually be technical in nature. Most of those are going to be case studies. There’s no textbooks, there are no books that serve as an entry point for the field or start with the basics. I felt that that was a problem and a void that needed to be filled. When I started in the field of off-grid systems I already had a PhD in electrical engineering, so I had a solid foundation of many of the technical elements, but not their application in developing countries or really rural settings.

Let me give you an example. If you think of a device like an inverter, it's a device that converts DC to AC in electrical system. So they're usually covered in textbooks on power electronics. But what I realized is that you might make very different designs decisions if you're going to use an inverter in someone's garage or in an industrial facility, then in an off-grid system. For example, most off-grid systems are not in temperature-controlled environments. Because of this, you might find that you would design that inverter differently or use it differently if you knew it was going to be in an off-grid situation. But that really was omitted from most of the textbooks that are really written for Western audiences and very mature economies.

In developing countries, it's also very common to find square wave or modified sine wave inverters, but textbooks don't cover that. So, I found myself despite having a solid technical background, it wasn't in the context that I was really interested in. There was a gap there.

It was also challenging jumping from source to source, white papers, reports, standards to see the complete picture of how you might implement off-grid systems. There were just a lot of gaps and I felt that this was a substantial barrier to the industry. I saw a need for there to be like a single book that would pull all these different aspects together. These technical aspects such as, how solar panels work, how wind turbines work, batteries, inverters, charge controllers, and putting them all into one place with a single narrative using consistent terminology and then written explicitly for the developing world context. That's the first reason why I wrote it.

The second reason is that if you look at projections for how many off-grid systems are needed to end energy poverty, it's a staggering number. I mean, we're talking about hundreds of thousands of mini grids alone.

And so even if we had the capital and a favorable regulatory environment, do we really have a workforce that's ready to do this? Are our engineers prepared? Are our entrepreneurs prepared? And so I felt like a textbook would be one way that I could really contribute to the industry.

And then lastly, if there's anything that I love more than learning, it's teaching. Anybody that writes a textbook will tell you is very challenging and you learn so much in that writing process and I really enjoyed the experience.

Distributing Solar: Does it cater towards the students you are working with at university? Or are you really looking to have engineers or maybe students in emerging markets to be using the textbook?

Henry: When I started writing the textbook, I definitely had students in mind - that is to say students in their third or fourth year of their undergraduate education or maybe some graduate students even. If you look at the book you will see that it has some elements that you would expect to see in any textbook. There’s worked out problems, exercises, lots of equations, figures, images and that sort of thing. I also devote a few chapters early on describing the context of energy poverty. I teach a class with the book and I find that this topic resonates really well with students. I think students are always eager to see how what they are learning can be applied in the real world and I think the idea that what they are learning can be used to solve a global problem is really inspiring to them.

But I also wanted the book to be a resource for practitioners. I think very few people in the industry have any formal training in off-grid system design and implementation at least from the technical engineering side. So, the book has a very practical bent to it. For example, I spend time talking about how to interpret specification sheets of batteries and solar panels, a lot of the terminology manufacturers use, and I also include a lot of best practices. So, I do get a lot of feedback from people in the industry saying they found the book useful as a reference. You don’t need to be an engineer for the book to be of value to you, but it certainly helps if you are not afraid of the technical details in it.

Distributing Solar: You’ve mentioned already that very few people working in the sector currently have formal training either in electrical engineering or with these systems in particular. What do you typically find their training has been? How do people typically learn to put together energy systems, is it all on the job practical training - learning by testing and from other engineers who are already working in the sector - or is there also a group of people who are coming out of university with some understanding about electrical systems and then are applying it to their work?

Henry: I think it is a little bit of all of the above. It also depends on when someone would answer that question. Ten or fifteen years ago it seemed it was all on the job training. That’s how more or less I learned and with a lot of the companies that we worked with early on it was clear that they were still learning as they were going. I think nowadays it is maybe a little bit easier. There’s some graduate programs that pay more attention to this but I still think that it is quite limited. I think that there are only a handful of universities particularly at the undergraduate level that have courses on how to design off-grid systems in the developing world context. Many of them use my textbook so I have a sense of who they are and where they are located but it is not a core part of the curriculum yet. I think that is a shame because students are extremely interested in the topic and you are teaching a lot of the same engineering principles that you would teach in any other engineering course, it is just for an application that is often overlooked but excites students tremendously.

Distributing Solar: Is that typically in emerging markets or do you mean students in the US and Europe?

Henry: All over. I think it is especially useful for students in emerging markets because they are going to get it and they are going to see the application of it. They will have the opportunity without needing to get on a plane and go somewhere else to see the challenges in off-grid living. And really that is the type of person that I hope this book would resonate with. The type of person that I hope would pick up the book and it would give them enough information to get started to go work for a company or start their own company that can work to provide off-grid electricity access.

Distributing Solar: You’ve mentioned already that you teach a class that is focused on off-grid energy access and electrical systems. How well does your academic work in Seattle interact with the work you are doing in developing countries? Do you have a lot of opportunities to go between countries, to go between Sub-Saharan Africa for instance? Do you work on projects there or is it primarily on a remote basis, through teaching programs?

Henry: I am very fortunate to be at a university like Seattle University that really values this type of work. They don’t just see it as a pet project or a hobby, I am able to integrate it very well into my teaching, very well into my research, and I think it is a service that the university values. They see that it helps get students engaged, they see that I am one of the early pioneers of writing books and putting out educational material on it and that it is not something I just do as a hobby. I am fully invested in it.

Distributing Solar: You provide some trainings to organizations working in this space as well. Can you tell us more about these trainings you provide to organizations working in off-grid solar and off-grid energy? What is the focus of the training, what do you cover, how does the training work, and maybe just give us some details about the types of trainings you have provided?

Henry: I have spoken about off-grid systems all over the world and it is often associated with a conference so I will do a half day or full day tutorial. Sometimes it can be a seminar at a university or a guest lecturer or for a professional association, I do a lot of those every year. Last year I even teamed up with an organization called Engineering for Change and gave a six-part webinar series on the book. I’ve spoken with school groups as young as middle school.

Regardless of the group I try to cover three general things. First, I introduce the context of energy poverty. Second, I cover some technical aspects. Obviously the depth varies based upon the audience, but topics might include: How solar cells work, the electrochemistry of batteries, how to estimate the load of users, the resources that power the wind turbines or PV arrays, and the mini-grid life cycle and design aspects. So, we can get pretty deep in the technical meat of it if the audience has a technical background. And lastly, I really like to share examples of experiences that I and my colleagues have had in actually doing these systems - what to do and what not to do. Sometimes I co-present with experts on economics or the social implications of off-grid systems. So, I do this a lot and I love doing it. If people are interested, I have a bunch of material on my website that people can access for free. If you're interested in having me talk to your group, please reach out to me and we can see if we can work something out.

Distributing Solar: In the book you provide an overview of a number electricity generation options. I think typically when people talk about the off-grid energy space they often think about solar, but as you noted in your book there are other technologies associated with this space from solar to hydro to wind to biomass. Could you tell us a bit about what are the factors to consider when you're choosing the generation source and how have you seen this dealt with in practice?

Henry: Sure. Selecting the generation source is perhaps the most important technical decision that gets made in an off-grid system. My advice would be that you shouldn't let your background or obsession with one type of generation source dictate what you use. In other words, just because you have a background in wind doesn't mean you should by default use wind. The saying is that if you have a hammer, everything looks like a nail. You really shouldn't be doing that.

To select the source that you are going to use you would first consider the quality and availability of the underlying resource. So PV / solar, for example, you need to know the average irradiance, the strength of the sunlight and how that varies over the year. And this is really easy to do nowadays with so many solar databases and online tools that are out there. My group, we use HOMER and you just put it in the latitude and longitude, and you get a very reliable data set for that particular location. Solar, I think is the easiest and that is one reason why you see it used so much - it's quite easy to get the data on the solar resource.

Wind is probably the most tricky, and I think that's probably partly due to the fact that there is a high sensitivity between wind speed and the power in the wind. It's actually a cubic relationship.

So, if the true wind speed is half of what you thought it would be, the power in that wind is actually an eighth of what you thought it was going to be. And that's a huge swing so mistakes are really costly. And the wind resource varies locally very quickly: it might be really windy in one place and then 50 meters away it might not be suitable at all.

And so, you can't really use a wind resource map online to know if a particular location has an adequate wind resource. It's just really difficult to do the siting of your wind turbine. What you really need to do is to set up a tall meteorological tower, 10 or 20 meters tall, for example, and then measure the wind speed. Because speed can vary throughout the year, you really should measure it for a year. And that is a huge barrier to using wind. Now, obviously there's going to be a few locations where you know it is a strong resource and you don't need to do that, but having to set up a met tower and record the data for a long period of time to see if it's windy, is usually prohibitive for any organization that wants to implement a lot of off-grid systems.

Even something like a diesel or a petrol genset has availability needs to be considered as well. Let's say you plan on using a gen set. Well, you need to ask yourself how easy is it to get the fuel to that site? Is it possible to do that during the rainy season? Where can you store the fuel? Can it be stored safely? You would also ask yourself does this country have fuel shortages that occur? How volatile is the pricing? and so forth. Whatever resource you are thinking about, you really need to consider the quality and availability of it. Then once you understand that, you start looking at other factors like the capital and operating costs. You might rule some things in, or some things out based upon how much it's going to cost to do.

Other considerations would be the lifespan of the components. Is this something that you want to maintain and possibly replace every few years like a genset? Or you need something that will last 10+ years like a solar panel?

Distributing Solar: Do you find that the companies that you work with are actively considering these technologies and thinking critically, about what is the best technology to be used? Or are they constrained by other factors such as where can I get the parts and which technologies do you know about and have heard about?

Henry: Most of the companies that we work with and in the regions of Sub-Saharan Africa that we are involved in, the real obvious choice is solar. We have a feel that this is probably gonna win out, but if we were in a location, for example, that had a hydro resource, I think we would give that a hard look. Micro-hydro is an excellent type of generation if the water resource is there. But a barrier to micro-hydro of course, is that the whole system needs to be custom designed. You need to figure out how you are going to get the water from the stream all the way down to your turbine. And that is a custom design job. And you might need to have a custom-made turbine as well, so that it is compatible with the water resource and your generator and all of that.

I think if you look at the industry, most of what you see now are companies that are specializing in solar. That makes sense because most of the places where we have a challenge with electricity access, there's a really good solar resource. So, that's sort of the first one that you look at, but there could be other ones that are viable as well. I think some mistakes that I've seen are people that are just obsessed with solar. For example, we would talk to an organization that maybe is building a school or a medical clinic, and they want to put solar panels on the roof. So, we do some advising for them. And we dig a little bit deeper and we see, well, wait a minute, the grid itself is 50 meters away or a hundred meters away or something like that. Why not just connect to the grid? It's going to save you a lot of money mostly because the grid is going to be subsidized. And if the grid isn't reliable, then just use a battery or inverter system. But some people don't get over that. They say, well, we are going to do solar, even if it's much, much more expensive. They don't even consider these other options, like a grid connection, or even a backup diesel generator set, which might only run a few hours a year, but could save a lot of money and capital costs.

Distributing Solar: What are the most common misconceptions or misunderstandings about off-grid energy systems that you have encountered? And what would you really recommend that people think twice about before assuming that for example, as you say, solar is always the best option or the best solution?

Henry: I think there's a lot of misconceptions and misunderstandings out there, especially for people that are new and some people that have been in the industry for a while. I'll pick out a few. I think there is a misconception about system availability or reliability. I think there is a tendency for engineers to over-engineer systems. It seems natural to want to design an off-grid system that's available 99% of the time or even more. But in reality, increasing your availability by a few percent, say from 97 to 99% could actually increase your capital costs by maybe 50% or more just because you need larger batteries and panels. There's actually some research that I've worked on that has shown that for some cases. So, striving for extremely high reliability is really limiting the impact of your resources. And most of us don't have unlimited budgets, right? So, you are impacting fewer people because you want your system to be so over-designed and so available.

I think really understanding that trade-off between your upfront cost and the reliability of the system is important. You should also be comfortable saying, “Well it’s ok if our system isn’t available every hour of the day in the rainy season. I think in most countries where electricity access is a problem, the grid is nowhere near 97% reliable. It could be far, far lower. So, if you are really trying to have a broad impact you need to understand these trade-offs.

I think another misconception is over relying on surveys to estimate the load of an off-grid system. Here's what I mean, let's say that you're planning on implementing a mini grid.

In order to properly design it, you need to have at least an estimate of the average daily load. How much electricity are your customers or your users going to use? A very natural approach is to survey these users. What you are trying to do is estimate how much electricity they are going to use based upon the devices (lights, television, radios) that they plan on owning once they have electricity, and how long each day are they going to use them.

And this seems like a very reasonable approach and indeed it's an approach that many organizations take, but research has shown that this is a really unreliable way of doing it. I've worked on studies that have shown when you use this method the average error is often over 300%. I mean, that's actually 300% on average. It's not like there's just one or two people that are really bad at estimating their consumption, but hundreds of percent higher. And so if you think about it, that means you're able to serve far fewer people with that same amount of money because your system is really over-designed.

There's lots of potential reasons for why this survey method is really error prone. Just as an example, or one way of thinking about it is if you went to the average American and said, “How much cow dung or kerosene would you use if you didn't have electricity”? Do you think that people would have a reasonable response or an accurate response? Probably not.

In the research that we have done, we found that people are not very good at estimating the amount of time that they are going to use a device or accurately predicting what devices they will have. In fact, we did research where we did a pre implementation survey where we tried to estimate their load or predict their load and we compared that to what they actually used. And it was off by a couple hundred percent. But then we revisited them after the grid had been installed and redid the survey. So now they know what appliances they have, and they have

some familiarity with electricity because they have been using it for the past year, for example. And we asked them to, again, estimate their hours of use. Even after doing that, we were off by about a hundred percent. So, it is just not a really reliable way of doing things. And you see people designing systems based upon these surveys, believing perhaps that the value that they calculate are true and instead they really need to take it with a grain of salt.

Distributing Solar: What are the alternatives that you would suggest other people use if they can't use the survey approach, which I think is pretty commonly used in many countries or many companies?

Henry: Yeah. It is extremely common. I think really what we showed in our research was that we were not trying to advocate against doing it.

I think there are a lot of benefits to visiting your potential users and talking to them about how they plan on using the electricity once they have it. Even generating that estimate is a useful exercise, but you have to take it with a grain of salt, and you have to be skeptical of it. You can't be surprised when the value of an average daily load doesn't match what you thought. You can do surveys, but just understand that the value calculator is going to be very error prone and probably an overestimate.

Luckily, there are some alternatives and the most promising alternative that is being used by some of the bigger players is to take a data driven approach where, if you have done this enough and you have remote monitoring in place, you know the hourly or the daily consumption of each of your users and you start having some historical data that you can look back on. And although you are providing access to a new village, maybe you have a village that you already worked in that was similar. So, you just take that village that you have worked in as a proxy for the new village and you do your estimation based upon that. And we actually did that in one of our studies and we saw that that was the most effective way of predicting load is just looking at similar locations in the past and what they use.

But of course, in order to do this, you need to have had other villages or other communities that you've provided access to electricity to, or you need to have a database that's publicly available with that information. And that is still hard to come by, especially if you are a newcomer to the field.

Distributing Solar: You clearly have quite a bit of practical experience from your work in Sub-Saharan Africa and you have worked to deploy off-grid solutions there. In particular you have worked quite a lot in Zambia. Can you tell us about the work that you have done with KiloWatts for Humanity?

Henry: Yeah. So, in addition to being a professor, I am president of a nonprofit organisation called KiloWatts for Humanity. We are a volunteer-run nonprofit based here in Seattle, Washington.

I founded KiloWatts for Humanity with two other people from Seattle University, Jenna Isaacson and Steve Sabia. KWH really grew out of the work that we were doing at Seattle University. Now, before I get into describing what KiloWatts for Humanity does, I'd like to offer a few thoughts about why we decided to spin off KiloWatts for Humanity as a separate entity from the university because this is one thing that I feel strongly about.

I think that international development projects in at-risk communities are probably not appropriate for most universities to be doing. I think in most cases, the mission alignment is questionable. Universities exist to educate and to conduct research and off-grid communities really deserve better than to be treated as sandboxes for intellectual curiosity or to serve as field trip destinations and photo ops for our students. Universities know that these pictures and stories and opportunities for their students are good for PR and attract potential students but that is really not what a project should be about.

I think that most students who might be very dedicated to working on an off-grid system or a certain community while they are in school, it does not carry over after they have their diploma. Very few come back to sustain a project that they were working on as an undergraduate. And then all it takes is for funding to change or a faculty member to leave before that community has that connection cut off. I do see a role for higher ed in off-grid electrification. I think students, faculty, and staff can learn and can contribute a great deal to ending energy poverty, but it needs to be done appropriately and sustainably so I think universities should partner with external organizations whose mission is to implement and sustain off-grid systems. This way it keeps the project focused on energy access and development and not on student learning. And I think it comes down to a difference between a project mentality and a program mentality, where a nonprofit is going to run these programs and it's going to be something that is baked into their core business whereas for the university it's sort of a side gig that they are involved in.

With this in mind, we decided to spin off KiloWatts for Humanity. We still work very closely with Seattle U and it has worked out well for both organizations, but we felt that it needed to be an independent home for this effort because it was so important. So, we founded KWH five years ago and our goal was to bring sustainable electricity to communities in developing countries in a way that fosters economic opportunity, empowerment, and dignity.

We have electricity access programs in four communities in Zambia, and one in Kenya. Our model is to partner with in-country nonprofit organizations. These are organizations that know the rural communities really well and are committed to them in the long term. We work with our partner to identify communities that we think an off-grid system would be viable in.

And believe me, just because a community is off-grid does not mean that they are a good candidate for an off-grid system, or at least one that will be sustainable. As a nonprofit, what we do is we raise money for the system, mostly through grants or individual donors, and then our engineers design the systems. And we hire Zambian companies to install the systems through a competitive proposal process. And at the end of the day, it is our partners that own and operate the systems, not KWH. In this way, it is really Zambians helping Zambians. It is not Americans parachuting in and saving the day. Our partners are really the face of the project. We try to be behind the scenes as much as we are able to.

We use what you might call the “energy kiosk” model of electrification. If you think of electricity access as a continuum, on one side of that continuum you might have Pico solar, and on the other, you might have large mini grids or even the grid itself. And an energy kiosk fits somewhere above a solar home system. So instead of being a few tens or hundreds of Watts in size energy kiosks are typically kiloWatts in size. They would fit in below mini grids because the reach of a kiosk is limited and in an energy kiosk there is no real distribution network. This obviously reduces capital costs and maintenance, but it also avoids a lot of regulations that come into play when you start selling electricity.

But what the kiosk does do is it provides power to a suite of businesses. We think of it in a way like a rural strip mall, and we are providing power to a number of shops. There are grocery stores that sell cold drinks or freeze meat, recharge cell phones, tailors, barbershops, hair salons, water pumps, ice makers. These kinds of things are powered by the kiosk. So, we really have that focus on spurring economic activity in the rural area.

This helps create jobs. A single system can spur thousands of dollars of economic activity each year in a rural village. We do work with our partner to develop a business plan with that local community so that some of the revenue from these activities gets put back into the system and gets saved for maintenance and replacement.

And then one of the other things that we do importantly, at KiloWatts for Humanity is that we offer free advising to organizations that might be interested in off-grid electricity. So as an example, we might partner with an Engineers Without Borders chapter that is working on a medical clinic. They are really good at designing the building, but they are maybe lacking the expertise in designing the solar aspect of it. We will work with them and we will come up with the design and share best practices and so forth. So, some of your listeners might be interested in reaching out to us, if there is a project that they have in mind and they want some advice on.

Distributing Solar: It was interesting to hear about off-grid communities sometimes not actually requiring off-grid electrical systems or an off-grid mini grid or even a solar kiosk. Can you speak a bit more about that and how you make your analyses on which communities you should go into and where there is the highest opportunity or potential for success?

Henry: There is obviously the need in so many communities and it sounds harsh, but the reality is that many of these off-grid communities are too poor to really sustain one of these systems. Now of course you could go parachute in an energy kiosk, solar home systems, solar lanterns, and walk away but we really want it to be sustainable and a key cornerstone of sustainability is financial sustainability. We know that the second you install those batteries the clock is ticking on when they are going to fail. So, without a good plan of saving up money to get the replacement for those batteries the system is going to fail in a few years, and I do not think that that is a good outcome.

In many communities there is just not enough economic clout to afford these systems. So, we look for ones that are able to do it. We look for ones that have an internal organizational structure that is supportive and conducive for an energy kiosk. Who is going to manage it locally? What kind of training do they have? What kind of training do they need? We look at social indicators. Is that actually what the community wants? We do focus groups, usually through our partners, we have them do surveys and we try to figure out if this is a need for the community, if this is a location where a kiosk can be sustainable in, and what sort of businesses might be powered or might be started up and be an off taker for the electricity. We look to see how far away the power lines are. We do not want to install a system and have the grid come just 6 months later. These are all factors that we look at in trying to decide which communities will be good candidates.

Distributing Solar: In a different life I also studied physics at school and university and so I couldn’t resist the opportunity to dive into some more technical terms. But, to make sure it is still interesting for our listeners I will run through some frequently encountered electrical or physics terms and for each of them if you could please give us a quick one-minute explanation, I’ll time you, and tell us why it is important.

Henry: I’ll do my best.

Distributing Solar: Great. So, to begin with, ACDC coupling.

Henry: One way of categorizing a mini grid is its coupling. And the coupling of a mini grid can be AC, DC or AC-DC. And it just refers to the nature of the electricity that is generated by the power source. So solar panels produce DC. They are going to be DC coupled. A hydro turbine is probably going to be producing AC so it is going to be connected to an AC coupled system. And if you have an AC-DC coupled system, it means you have a mix of DC and AC generation sources.

Distributing Solar: Great. That was only 30 seconds! That's very good. So, the next one, tell us about load factors.

Henry: The load factor, technically, it is the ratio of the average power to the peak power. And so, the load factor really never exceeds one, and it's usually expressed as a percent, but the load factor is useful because it relates two of the most important characteristics of the load, the average load and the peak load.

And what you really want is you want your load to not have a high peak, as a familiar example, you can think of a church and the saying goes, you have to make your church large enough for Easter. So, you build this massive church because you know, on Easter, you can't turn people away. And then the rest of the year, it sits sort of empty or not used to capacity. Right? You can think of that as the load. That is a tremendous waste of resources to have a really high peak that doesn't occur that often. You would rather be consistent, throughout the day, throughout the year, et cetera.

Distributing Solar: And next, can you tell us about grid-tie inverters?

Henry: Yeah. So, anytime you want to convert DC to AC you need a device called an inverter. Inverters come in all sorts of shapes and sizes and different types, but a grid-tie inverter is one where the inverter is smart enough to see if there is AC generation on the AC side of it.

So most mini grids, you do not need a grid tied inverter because there is no grid around you. You are the grid. But if you want to connect eventually to a grid, maybe your mini grid is going to expand, or the grid will eventually come to you. Then you need to have a grid-tie inverter and make sure that your wave forms are all synchronized and that you are controlling the exchange of power. For the most part though off grid systems really don't need grid-tie inverters.

Distributing Solar: Perfect. And maybe just a final one. Tell us about bypass diodes.

Henry: Okay. What a bypass diode does is it helps your array function when there is some shading on it. A PV array or PV module is made up of a bunch of individual cells, solar cells, and they are all connected in series. And so, if you have shade on even one cell, it acts like a bottleneck for all the current flowing through the other cells. So, a solar panel does not need to be totally shaded for its power to drop, it just takes one cell to be shaded. One way of overcoming that is you put in bypass diodes, which basically allows the current to get by that bottleneck.

Distributing Solar: That's great. I was going to ask you about single-phase full bridge rectifiers, but we’ll let your listeners look that one up in your textbook and leave that as a teaser.

Speaking about your textbook, I'd love to understand a bit more about the process of putting the book together and hearing more about how long it took and when you came up with the idea. So maybe if you could start with that, just tell us a bit about how long it took you to write the book and what was the process of writing the book like.

Henry: Yeah. I think that it took about three years from when I started the book to when I finished writing it. I think I had the idea in my head when I first started in the industry and was sort of frustrated that there wasn't one of these books already written. Once that idea was in my head, anytime I did any field experience, I thought, “Would this be something I think I should talk about in the book?”.

So, I took a lot of pictures and I kept a detailed notebook of topics that I thought could have been interesting. And the book really came together when I was doing my Fulbright in Zambia, living in Zambia. And that is when I sort of started formally putting together a book in terms of class notes.

I was going to teach a class on this topic when I got back to the United States and so that served as the main outline for the book. And then like any book you talk to a publisher and you come up with an agreement and then you just start writing. And I was supported by my university to do the book. I had an endowed chair position that gave me more time to write, and I just put my head down and I wrote for about a year. That was the main thing that I did for about a year and I am quite happy with the results.

Distributing Solar: Was it mostly information that you were already familiar with or had encountered in your field experience or was there anything that you needed to research or that was difficult or complicated?

Henry: So, you think you know everything, or you think you know a lot, and then you have to explain it in detail and you really have to know it. I had to do a lot of research. It was fun to do, it was really fun to just dig in deep. The writing of it was also a fun exercise because it was very different than writing a technical, peer-reviewed paper. One of my mentors made the comment that, “Great books aren’t written. They are re-written” and I kind of had that mindset of writing and writing and writing and then revising and revising and revising. Like any book, I look at it now and am proud of it, but there are certainly things that I would do differently in a second edition. Fixing little typos here and there but also adding other concepts that should have been included that I didn’t have the space for, or I might have presented a few things differently. But by and large, I am happy with it and I think it accomplished what I set out to do.

Distributing Solar: What are the kinds of topics that you wish you could cover that you did not have a chance to?

Henry: Well, I would have written more about some of the specialty applications. I do talk a little bit about off-grid vaccine refrigerators. I would've liked to have expanded that because you do see that a lot. I would've written more about solar pumps and applications like that. And I had a whole chapter pretty much written on development practices that more or less got cut. So, I would like to have a little bit more there. And then there is a final chapter in the book where I talk about some of these other considerations that probably could have been two or three times as long.

Distributing Solar: You've mentioned some in your book and I assume those were selected to be the most important, but can you speak a bit about some of these other considerations that you've mentioned, and which do you think are the most important?

Henry: So, like I said, this chapter could have been two or three times as long, but I was already at about 500 pages and that is plenty to write, but it was really fun to write this chapter.

The truth is that there are so many other considerations in implementing an off-grid system beyond the strictly technical. In this chapter, I really wanted to introduce some of these considerations and also offer some advice on how you should approach off-grid system development. So, let me talk about a couple, and some of these are covered in the book, but maybe not at the detail that I will talk about now, or maybe I will explain it in a slightly different way.

One topic in that chapter is the use of donated equipment. This comes up a lot when I am speaking with groups and they are doing their first project. This might be a student club or a church group, or some other nonprofit that maybe does not specialize in solar but needs solar power for their clinic or school that they are building. So, I usually will ask them, “How are you going to source the equipment”? And some of them will say, “Well, we have this connection with this solar manufacturer or some other business that can make an in-kind donation of the solar panels or the batteries”.

In some of the cases, this donation is what makes the project possible because it saves them thousands of dollars in costs. But I think what is overlooked is that the donated product needs to find its way to Zambia or Haiti or wherever. Usually, the manufacturer is not that generous to ship it for you.

So, this process really is not trivial and if it's not trivial, it is at the very least costly. It can add a tremendous amount of uncertainty to your schedule. I mean, weeks or months, and you do not have a lot of control over the shipping and what happens after it gets to port. Import duties can be 25% and so unless you have waivers and have figured out the waiver process, you are going to pay 25% of the value and that might not have been anticipated because the equipment was free. Once you figured that out, getting your equipment through customs can be a whole other problem. You might have to wait weeks or months and you are paying a daily holding fee and maybe the custom agent wants a bribe or something like that. Meanwhile, the batteries that had been donated to you are just self-discharging on a port somewhere. So, this can end up being a very bad situation. You also have to ask yourself, “Okay, what's going to happen if that donated panel or inverter or whatever fails? Was there a warranty that came with it? And even if there is a warranty, how do you get it back? How do you replace it?” and so I really try to discourage organizations from relying on these donated equipment, especially if the donated equipment is substandard in some other way.

Another topic I discuss in that chapter is capacity building. Off-grid projects offer the opportunity to do more than just provide electricity. One way that they can have a broader impact is by increasing the capacity of a country to do these projects themselves. That way it is not always foreigners doing it. But unfortunately, in a lot of projects that I see, especially done by organizations abroad, this capacity building part really is not there.

Instead of hiring, say a Zambian company, to install solar panels -and trust me no matter where you are going to be working, there is going to be a company that would be willing to install solar for you- instead of doing that, you bring your students or your volunteers or something and they do it. And I get it. I mean, there is an appeal of doing some work with your hands and it makes for great pictures and all of that, but the thing is, in most cases, students or volunteers do not really know what they are doing. They are not professional installers in the United States. They are not electricians. And even if they electricians, they are probably not licensed to do their work in Zambia or wherever.

I mean, just imagine that reverse scenario, would you let someone from a church group in Haiti come to your house and install solar panels or in your child's school or something like that? No way. They would need to have some sort of qualifications or warranty of their work. I think the right thing to do is to hire licensed, reputable, local companies to do it. You can still go to the installation if you want. In fact, you probably should just to do your due diligence to make sure that the company is doing what they said they were going to do. And even just going for the commissioning can make for some very lovely pictures if that is really what you are interested in, but you have this added benefit of supporting the solar company.

Keep in mind that company really has to compete with free volunteers from organizations that do solar from abroad. Right? So, they are working against these nonprofits from abroad and it is really hurting. So, I would really encourage organizations to avoid this reverse outsourcing scenario.

At KWH when our volunteers travel, they are not installing solar panel and batteries. We just do the commissioning as part of our due diligence. We do training and we will also install some specialty remote monitoring equipment that we use for research. But other than that, it is all local people that we hire.

I think one more consideration that is important -and this is really a mindset to have- is that you need to realize that there is an opportunity to do more harm than good when implementing an off-grid system. The technical aspects are often the easiest ones to resolve. Keeping that in mind is extremely important. You have to think about ways that what you are doing could actually be harmful and then think twice whether you should really be doing it if that is the case.

I often use this example. Whenever I travel abroad it is always fun to take a camera or a phone and take pictures, especially of the kids and show them on the screen what they look like because in many of these areas they do not have mirrors at home or anything like that. It is a good way to interact with the people. I always felt that this was such an ephemeral experience. You just show them the camera and they get to see what they look like and then you kind of walk away. And so, what I did was I thought, “Let’s find a way to make this more lasting”. And I researched this pocket-sized printer where it is Bluetooth connected to my phone and it is basically a polaroid camera. So, I could take a picture and then wait a few minutes and print it out and give it to the person that I took a picture of.

After I got this printer, I went back to one of these communities and there were a lot of children playing so we took a picture of the kids playing and printed it out. We said, “Ok, which one of these kids do we want to give the picture to?” and my colleague Peter said, “Let’s give it to this kid in the green shirt because he’s got the best smile in it”. So, I handed the picture to the kid in the green shirt and then what happened? What happened was that all the other kids started punching him and trying to take the picture away from him. Now it wasn’t that bad, they were kids, and they were kind of playing around, but still, it speaks to this idea that I have the technology right. I knew what technology I needed to accomplish my goal. I needed to have a Bluetooth connected printer and my phone and all of that. I had the technology right but in that moment, I just lost sight of -what is obvious to me now as a parent- of what would happen by doing that.

If you think of your off-grid systems, you can get the technology right but if you are not thinking of the ways that the use of that technology or the presence of that technology could go sideways, you could be doing more harm than good.

But I did learn from that and now whenever I do that, I do family portraits and I give the picture to the mom because no one is going to mess with the mom. You learn from your mistakes.

Distributing Solar: That is certainly a very interesting and very important to think about, as a lot of people have noted about the sector. There is what I think of as a romanticization of people living in off-grid communities or in unelectrified areas and I guess we often think we have the ability to just go over and solve their problems magically as you say, not realizing the context or what is actually going on in more detail.

You very deliberately titled your book Off-Grid Electrical Systems in Developing Countries and noted in your preface that “developing countries” often has connotations of being either degrading or sometimes being used in a negative way and I think terms like “emerging markets” or “frontier markets” are now more commonly used. Can you tell us about how you think about that and why did you decide to use the term “developing countries” still?

Henry: Well, as I write in the book, I am not completely comfortable with the term “developing countries” but ultimately, I decided to use it because I did not think there was a better alternative, especially for the title of a textbook. I did not use “emerging markets” because countries like Mexico, China, and even Russia are usually considered emerging markets, but these countries also have high electricity access rates. “Frontier markets” is perhaps a better term. Countries considered frontier markets generally also have low electrification rates, but I think that term in and of itself is less familiar. I think when we use the word “market” it tends to cast the families and communities and countries that struggle with electricity access in terms of dollar signs and not people. I honestly think that sends the wrong message.

But of course, “developing countries” has its own baggage. Some people think it is a derogatory term, but many others think it is empowering because it shows opportunity and potential. That is the side of the interpretation that I fall in with. The more hopeful side. And of course, by “developing” I do not mean that to mean that a country has an immature cultural or familial tradition. I also do not presume that the so called “developed countries” are free from problems involving equity, access to education, healthcare, and so on. Lastly, I will point out that “developing countries” is the term that is suggested to be used by the Associated Press style guide. I think that speaks to the fact that although there is not a strict definition of “developing country”, many people have a sense of what you are talking about, so I felt that that was appropriate to use as the title for the book.

Distributing Solar: And finally, how can people get or access a copy of your book?

Henry: As part of Springer’s initiative to contribute to easing the COVID-19 pandemic they have made 500 textbooks available online -the digital versions- so between now and least July my book is one of those 500 so anyone can access a free full online copy of the book. I think maybe we could include a link as well.

Distributing Solar: We would love to close the conversation by asking you to some what we call “quickfire questions” to get a better understanding of you as a person, your background, and some context behind you. So, just to start us off, where did the name KiloWatts for Humanity come from?

Henry: I remember it very well. We were spinning out of Seattle University and we had a meeting of people that had been involved and we had to come up with the name and Steve Sabia came up with a list of options for us -He is one of the cofounders- and we voted, debated on what we liked, and KiloWatts for Humanity won by a landslide.

To me, I really like how we use the acronym KWH because as an electrical engineer, that's Kilowatt-hours. I think for the “blank for humanity”, is so that people know what this is, they are not surprised that we are a nonprofit and it speaks to what we do. You get sort of a sense that, “Okay, maybe this is a somehow electricity related nonprofit” and that is what we are in the simplest terms. So, I love it. I really like it.

Distributing Solar: Are there any books that you recommend to our listeners or books that have changed your thinking around the off-grid sector?

Henry: Yeah. One of the first books that I read when I was getting involved in this was Out of Poverty by Paul Pollack, who unfortunately passed away last year. It is just an incredible book about his mindset when he was designing and distributing treadle pumps throughout Asia. He has got this great quote that he says, and it's “If you don't understand the problem you set out to solve from your customer's perspective, if your product or service won’t dramatically increase their income, and if you can't sell a hundred million of them, then don't bother”. And that ambitious “we need to find solutions that are user centric and that scale so rapidly, that should be our goal. That should be our aim”, the part that always really stuck with me is the “Let's see how we can make a big difference”.

And the other book that I have found really interesting is The Impact of Electricity Development, Desires and Dilemmas by Tanya Winter. This book looks at what happens to communities after electricity has come to them. Throughout the book she talks about all the different ways that people have changed socially after this community in, I believe, Zanzibar gets access to electricity. It impacted how they pray, and just having an electricity meter in people's houses all of a sudden, the government was much more involved in their lives because you'd have a utility worker come every month or so into your house and read the meter. The level of intrusion there was much higher. Other things like when people slept, how many meals they had, and even the frequency of intercourse changed when they had electricity. It is just a fascinating read if you are interested in the non-technical aspects of electricity access.

Distributing Solar: So, to close our conversation, what are your predictions for the off-grid service sector for the next five years?

Henry: Well, let me tell you about my hopes, not my predictions. I am terrible at predictions, even though I worked for a wind forecasting company. Here are my hopes and I am going to take more of a philosophical approach to all of this so I am not going to throw out numbers of people that have access or whatever, but I want to talk about some of the discussions that we should be having as a sector. These come from sort of an ethical viewpoint, which may be related to my employment as a Jesuit university.

I think we need to be talking about e-waste more than we are right now. What is going to happen to these tens of millions or hundreds of millions of solar lanterns and solar home systems when they fail? What is our pathway for that, realistically? Because if you spend a lot of time in a rural community, you will see batteries just sort of discarded in the brush here and there and it is not like they have a good infrastructure for handling waste in general or e-waste in particular. So, what is our plan as a sector for this? Where do we see it going? There are conversations that are surely happening right now, but I would really like for it to be given more attention.

Another issue that I think we need to be talking more about is the ethics of data collection. With the solar home systems that have remote disconnect pay as you go, we are collecting a tremendous amount of information from these customers, and I think we are going to be using them, and are already to some extent using them, to generate credit profiles, which is going to unlock a lot of finance for these people. But do they really understand that we are collecting this information and going to be using it in that way? It gives me pause, if you think about some of the tech companies that are having a bad record of protecting data-privacy dipping their toe in this area. So, I think we need to think about this from an ethical standpoint.

Sort of related to that with remote disconnect, well, let us just say that the utility here in Seattle has a tough time disconnecting anyone from electricity and I think that is a fair regulation to have because people are so dependent on it. But with pay as you go and remote disconnect, it is just code in a program and it just disconnects people. We really need to think about the ethics of that. I know in many parts of the world that, say natural gas, for example, or heating oil is a lifeline, and you cannot disconnect people in the winter when their livelihoods really depend upon it. So, we should examine these issues as an industry, and come to some sort of conclusion or at least examine the pros and cons in a more formal way than we have done. We've just sort of assumed that if it limits our risk of investment, then it is a good thing, but we really need to be thinking about some of these other more energy justice related issues. I really hope that in the next five years, we make good progress on having these discussions.

Distributing Solar: I think that is a really important note to end on and as you say exactly right, often overlooked within the sector and within the industry. So, thank you for bringing it to our attention.

Thank you so much, Henry. You have been really generous with your time and it has been really fascinating and enjoyable to hear about both your experiences and your thoughts about the sector. Thanks for joining us on Distributing Solar.