The wizards at MIT have come up with yet another project that is nifty, cool, and eminently practical, with the invention of a simple, homemade $17 solar cooker designed for use in rural areas. The only materials are Mylar coating, yak wool, and bamboo ribs. In many countries across the world people cook with materials that are unhealthy both for themselves and to the environment, and this cooker aims to provide a cheap solution to that widespread problem with clean energy. And for an additional cost it will also be able to provide heat to homes. If they can get it into widespread production and find some funding, a huge amount of humanitarian benefit could come from this device.

The great sums of money going into research and development for solar technologies is an obvious reminder that the problems of the world are not only going to be solved in a low-tech manner, but it’s nice to have a reminder from time to time that innovations can come outside of a laboratory. The central premise of solar energy is so strong and adaptable that there are ways to apply (and improve) it across a wide spectrum.

Meanwhile, as always, solar technology writ large is improving, getting more powerful and more cheap. NASA is even ready to test out a solar sail to propel satellites and deep-space missions. With all of these creative solar solutions to difficult problems, the straightforwardness of the vast majority of solar projects is becoming more evident. Solar professionals are going to be able to handle powering vast portions of this country, sooner than people think. All that’s necessary is the money and the will to fulfill the potential for all of this ingenuity.

If you live in California and have wondered how you could afford to install photovoltaics but have been stopped by either a scanty bank account or fear of re-mortgaging your home, you might have just run out of excuses. The state has just enacted legislation that now makes it possible for homeowners to obtain low-interest loans from local government for the express purpose of installing renewable energy or energy efficiency measures. What is really innovative about this, though, is how you pay for it: you can pay the loan back through your property taxes over time.

One question we often hear at Getsolar.com is, “What happens to my solar system if I decide to sell my house?” You can’t take it with you, of course. The idea is that the system adds so much value to your home that you recoup your investment with a much higher sale price than you could otherwise ask. Under California’s new law, though, the solution is simpler–you just pass the outstanding balance on the loan over to the next homeowner. Technically it amounts to the same thing for the person buying your home (whether it’s an additional $15k built into their new mortgage or attached as separate state loan, they’re still taking on that money), but for you, it means you’re pretty much installing solar with no strings attached. Your home will still look competitively priced on the market if you ever need to sell, and you don’t have to quietly seethe about how you didn’t get your “money’s worth” out of your system before you moved. It’s like pro-rating your system for the time you’ve actually used it. How cool is that?

Perhaps I jumped the gun in saying “if you live in California…” While I have no doubt that other municipalities will follow suit, the two that are blazing this trail are San Francisco and Palm Desert, two very different communities (demographically and politically). The bill that the Governator just signed into law simply allows local governments to make this sort of funding available, rather than mandating them to do so. I hope the trail being blazed is less of a Route 1 and more of a Route 66 phenomenon–that is, nation-wide. This sort of loan is exactly what many homeowners need to make the jump to solar energy: it lowers the risk of the investment and makes something that seems, for some people, desperately out of range, suddenly a lot closer than they thought.

For more information:

Los Angeles Times

San Francisco Chronicle

Having just returned from the countryside, I already miss its bitingly cold, naturally clean water, its lush vegetation, its air free from the brown dust that characterizes Beijing. To be fair, Beijing hasn’t been so terrible lately—the past several days have been a striking blue—although every time a car passes by me on the street I still have to close my eyes for fear of dust or dirt blowing into them. However, Beijing’s neighboring villages still feel a world removed, and not just because horses roam the uneven dirt paths and roosters signal the advent of morning. The air even smells different: when it doesn’t reek of manure, rural air smells like mountain water and moist vegetation. For these reasons, I am especially glad that Beijing’s countryside has gone solar, and that its inhabitants have electricity and hot water without the polluting side effects of fossil fuel usage.

In the village where we lodged, as well as the neighboring gorge (both places quite popular tourist sites) and the surrounding villages, all of the street lights are powered by small solar panels. There are no traffic lights, but the lights signaling the arrival of trains are solar-powered. Solar hot water heaters cover at least half of the village rooftops. We stayed in a farmer-run inn—a number of the families in the village run their own inns out of their homes, and serve traditional home-cooked meals with the organic fruits and vegetables from their own gardens (this weekend, I had some of the best cucumbers and plums I’ve ever had in my life). At the first place we stayed, the owners proudly informed us that the hot water was solar-powered, so we would have hot water whenever we liked (the sun is quite merciless out in rural China). We eventually moved to a different inn, since one of our rooms didn’t have running water. But the fact that solar is such an ordinary way of life in this village, as commonplace as a television set or an air conditioner, feels simultaneously anachronistic and heartening. Not everyone may have gone solar, but it’s accessible to most.

Living in Beijing right now has made me rather ambivalent toward China’s environmental policies. It doesn’t come as a surprise to anyone that the PRC isn’t the poster country for eco-consciousness. Almost everybody drinks their water either boiled or from a bottle, and a blue sky day in Shanghai or Beijing is a rare day indeed. To its credit, however, the planet’s largest consumer of energy is attempting to clean up its act through measures such as a nationwide plastic bag ban or putting on a Green Olympics, and, most inspiring—or paradoxical—of all, being home to several solar cities. And no, these solar oases are not showpieces, developed solely for admiration during the Olympics. Here are but a few of the most well-known.

Kunming, the capital of southwestern Yunnan province, has been referred to as China’s “Solar City,” although it is not by any means The solar city. But with more than half of the city’s 4.7 million inhabitants all using solar hot water systems, and nearly every single apartment complex sporting at least a few on their rooftops, it’s not an undeserved title. Yunnan Normal University’s Solar Energy Research Institute, founded in 1971, houses laboratories focusing on solar thermal, solar photovoltaic, biomass energy and environmental engineering. Yunnan Normal is also home to one of China’s three National Solar Water Heating Testing Centers, which provide free testing services to the solar industry in order to facilitate product certification. Thanks to government incentive programs encouraging technology development, updated building codes and product certification centers over the past thirty years, the solar thermal industry has matured as nicely as it has up to this point. Thanks to a ruthlessly competitive domestic market, low manufacturing costs and China’s abundant sunlight (even Beijing receives lots of sun, for all its smog!), the price of a typical solar hot water heater—not including installation fees—fell to 1,600 rmb (~$235 US now) by 2007. There are clothes that cost more than that.

In more recent developments, there’s also the northeastern city of Weihai, in Shandong province, which hopes to become the largest solar city in the world. With help from Australia’s BP Solar, China seeks to emulate Australia’s Solar Cities initiative, which was responsible for the solar development of a Sydney suburb and the city of Adelaide, among others. There’s a lot of official hoo-hah in BP’s press release, but the figure that stands out most from it is the deployment goal of 100MW of solar PV, solar thermal and “energy efficiency applications.” Announced in April, the project is apparently still in the fuzzy planning stages—as evidenced by a lack of online information—but we’ll keep our eyes peeled for more details as they surface.

And now, the best for last. Behold, the pride and joy of China’s State Environmental and Protection Agency (SEPA): Rizhao, a coastal city of three million in Shandong province whose name means “sunshine.” Both Renewable Energy World and Inhabit profiled it last year, but a city in which 99 percent of its inhabitants use solar water heaters and whose traffic, street and park lights are all powered by PV cells deserves a second (or third) look. What originally first came as a shock to me is the fact that Rizhao incomes are not high. Considering that America’s model “green” cities—San Francisco, for one—are hardly the playgrounds of the poor, I was surprised when I read that per capita incomes in Rizhao are lower than the Chinese national average and even lower than neighboring Shandong cities. But then it made sense: Rizhao’s mayor, Li Zhaoqian, wanted to increase the city’s efficiency and save on energy costs, and save he did—as of 2007, the city reduced 52,860 tons of CO2 emissions from solar water heaters alone and saved about 9,333 rmb ($1,807 US in 2007, $1,372 now) annually.

The city now stipulates that all new buildings must incorporate solar panels, and strongly encourages government buildings and officials’ homes to be the earliest adopters. Although the municipal government played a large role in Rizhao’s successful solar development by raising public awareness of the benefits of solar through campaigns and education, Rizhao’s going solar was also a consequence of provincial governmental policy and the growth of its local solar industries. Because the local government lacks the financial power to provide the costly subsidies required to subsidize solar panel end users, Shandong’s provincial government subsidizes instead the research and development of the solar hot water industry in order to lower unit costs. In Rizhao, a solar water heater now costs roughly 4 to 5 percent of an urban household’s annual income and 8 to 10 percent of a rural household’s income. The provincial government works with local solar panel companies to lower costs, as well. Not bad, considering how China’s environmental disaster is in large part due to provincial officials’ refusal to comply with national environmental laws in order to turn a profit.

Since Rizhao went solar in the early 1990s, it has not only been designated by SEPA as China’s Environmental Protection Model City, but has also attracted increasing amounts of foreign investment and tourism. It has also played host to several international and domestic sporting events and has attracted several high-profile Chinese universities and professors to build campuses, complexes and homes on its soil.

Of course, a similar success story occurring in the U.S. would be difficult to come by in the same manner. Labor and materials, after all, aren’t quite as cheap here. Yet, with the right support in the appropriate industries and development of low-cost, high-efficiency daily appliances, perhaps an otherwise unremarkable little city in the U.S. can undergo a similar transformation as well.

Researchers are finding a lot of promise in a technology that uses glass coated with dye to generate solar power. A pane of glass is coated with a special dye, which shunts sunlight to photovoltaic cells in the frame. Very cool.

The best news about this, though, isn’t just that it’s cool, but that this could mark a potential paradigm shift in the way people view solar, if this technology were ever to hit mass production. And that’s because, as I’ve gone on about in previous posts, solar has the challenge of integrating itself into people’s daily routines, and this technology completely addresses that challenge. There’s a psychological obstacle to putting photovoltaic panels on the roof, or anything else that in some way changes (and therefore has the danger of screwing up) the way someone’s home or living space looks. It’s not an impassable obstacle, and the legitimate aesthetic appeal, financial benefits, and environmental value of solar are why many people choose to make such a change. But with something like this, the threshold for adoption becomes much lower. No longer is the family in danger of being those strange people on the block with the big panels. They won’t have to compromise their careful decision-making regarding how the space around them looks and feels. It will be simple; the addition is literally transparent.

That’s why I’m excited about this in more than just a technical way. This could be a real game-changer, in the residential zone particularly. And if we think about dedicated structures, then glittering, beautiful buildings that are both aesthetic marvels and substantial power plants doesn’t sound to bad, either. Here’s hoping these guys can make it work.

There’s no more silicon shortage. Plenty of governments (even if our own is an exception currently) are heavily funding solar R&D. So why, in the year 2008, is solar still not cost-competitive with traditional energy sources? This question has riddled a major solar convention, held for the first time in North America this year and wrapping up tomorrow. Intersolar North America, like most of these events, offers both a trade show and industry conference to reach everyone from passers-by who might wander into the exhibitor hall, to industry veterans looking to attend in-depth workshops and network with their international peers. The opening remarks of the show, held in San Francisco, addressed the cost issue immediately. Unfortunately, no one had answers. As one well-informed attendee pointed out, as quoted in the San Francisco chronicle, “That’s the $64,000 question…The entire industry understands we need to get competitive with the cost of fossil fuels.”

We could use some international inspiration. The 209 exhibitors registered for the San Francisco show can sure fill an exhibition hall; but at this past June’s Intersolar Europe, held in Munich, a staggering 1,050 exhibitors participated. This was more than double the number that registered for the same show last year, but the San Francisco attendees would have to quintuple to match those kinds of numbers by next year. It’s true that the European show hosted members of over 40 nations, and perhaps that’s a bit extreme to expect on our side of the pond. But the gaping difference does point, I think, to what remains the basic problem with solar in America: no one’s doing it. If Americans started demanding solar as an option to the same extent Europeans have, maybe that would give the industry the push it seems to need to go from “building momentum” to “has so much momentum it kind of can’t stop and will just have to go over rather than around the pesky coal plant in its way.”

Yes, folks on the two coasts–primarily California and New England residents–are pursuing residential solar, and utility-scale solar is becoming increasingly popular in the Southwest despite legislative setbacks. And of course there are the lone wolves looking for solar who happen to live in Michigan or Texas, and with the cost of fuel, it’s no wonder. But solar still has not achieved the kind of momentum that it has in Europe, either large scale or small. We’re still pushing every step of the way, fighting for government assists and recognition, educating on very small levels–in communities where a solar plant is going up, neighbors asking Joe Solar what those strange things are on his roof–and while this is excellent in its own way, it doesn’t achieve the kind of large-scale dissemination of information that would help more Americans realize how possible it is for them to incorporate solar into their homes. Even if photovoltaics is out of the price range for many middle class families, solar hot water shouldn’t be. We’ve had national campaigns to raise water conservation awareness, forest fire safety awareness, Energy Star ratings awareness, ozone hole awareness, tap water safety awareness. Maybe it’s time we had one for renewable energy awareness.

The past couple weeks, I’ve looked at various options for financing the purchase of a PV system. This week, we’re gonna dig a little bit deeper into the numbers. (Bear with me. I’ll try to make this as clear and as un-boring as possible…).

Bottom line: before buying a system, you’ll want to know what kind of return on investment (ROI) to expect. For all the excitement around solar power, PV systems are still pretty darn expensive. And in some parts of the country, where sunlight is sub-optimal and/or incentive programs are non-existent, they may never produce a positive ROI. Our interest this week is the payback period–that is, the time between when your system is installed to when it has effectively paid for itself via energy savings. The purpose here is to sketch out the variables involved. Like most forms of analysis, the one presented here is as only good as its assumptions. It doesn’t pretend to be perfect. It does, however, introduce the concepts behind determining an investment’s payback period.

In line with the past two weeks, I’ll look at the case of a 3.6-kW PV system installed in San Francisco for a customer of PG&E. I’m making all of the following available in an Excel spreadsheet. Here’s a look at initial project costs:

Kyocera 180-watt solar panels: 20 units x $835 = $16,700
Mount Rail Kit: 4 units x $360 = $1,440
5000-watt inverter: 1 unit x $4,000 = $4,000
250-amp DC disconnect: 1 unit x $330 = $330
AC kilowatt-hour electric meter: 1 unit x $100 = $100
Copper wire and junction box: 1 unit x $350 = $350
Grounding wire: 1 unit x $150 = $150
Labor: 50 hours x $110 = $5,500
Subtotal: $28,570
Less U.S. Federal Tax Credit =$2,000
Less CA Rebate (PG&E offers $1.90/watt = $1.90 * 3600 watts) = $6,840
System Cost after Basic Credits = $19,730

OK, so upfront costs are about $20,000–a considerable chunk of change. Note that the credits available in California vary by utility, so some of you out there could receive a rebate of $2.50 or $3.00 per watt instead of the $1.90 in this case. Regardless, despite the large upfront costs, the PV system in this case reflects a payback period of about 11 years. Check it out:

ANNUAL ELECTRICITY PRODUCTION

Number of Panels: 20
STC Rating in Watts Per Panel: 180 watts
Total kilowatts per hour (assuming optimal conditions): 20 x 180 = 3.6 kW
Expected performance (in real-world conditions): 80%
Adjusted kilowatts per hour (in real-world conditions): 80% x 3.6 = 2.9 kW
Average hours of sunlight (in San Francisco): 8.2
Estimated kilowatt-hours per day output: 8.2 hours x 2.9 kW = 29.5 kWh

Estimated kilowatt-hours per year: 365 days x 29.5 kWh = 10,775 kWh
Avg. California electric rate (PG&E, per kWh, 2008): $0.14
Estimated Income (Year 1): 10,775 kWh x $0.14 = $1,508
Average Electrical Rate Annual Inflation (assumed): 4

From here, essentially what you do is estimate the energy savings (taking account of 4% price inflation) over the next 20 years or so. Because of space constraints, I’m not able to show the full analysis (for more details, see the spreadsheet). Here’s an idea of what it looks like:

Year 0 (2008): -$19,730
Year 1: -$19,730 + electricity sales ($1,508) = -$18,222
Year 2: -$18,222 + electricity sales ($1,569) = -$16,653
Year 3: -$16,653 + electricity sales ($1,632) = -$15,021
Year 4: -$15,021 + electricity sales ($1,697) = -$13,324
Year 5: -$13,324 + electricity sales ($1,765) = -$11,560
…
…
…
Year 10: -$3,766 + electricity sales ($2,147) = -$1,619
Year 11: -$1,619 + electricity sales ($2,233) = $614
Year 12: $614 + electricity sales ($2,322) = $2,936

As you can see, our 3.6-kW system “pays for itself” in about eleven years. A few points are necessary. First, though this is a pretty rough analysis based on averages, it drive home the main point that solar PV systems can and do represent a favorable investment. Second, in the interest of simplicity, I omitted the fact that at some point in the first 10 years or so, you’ll likely have to replace the inverter. This tacks on another $4,000 in today’s dollars to the analysis, and pushes back the payback period by a couple of years. Third, I assume that retail prices for electricity will rise about 4 percent a year. It’s not implausible, however, that price inflation in electricity markets will be higher. In this is the case, the value of your PV system will naturally be higher and the payback period shorter. Solar power reflects an effective way for residents (and businesses) to hedge against price uncertainty.

That’s about it for this week. If you’ve got any questions, don’t hesitate to ask. Next week I’ll expand the analysis here a bit further, looking at net present value (NPV) and alternative scenarios that reflect different assumptions on price and system performance.

This may be idle speculation, but it’s very exciting and very cool idle speculation. Looks like a rumor of a solar Toyota Prius is picking up some momentum.

I’ll agree with the author of the article on the basics. This isn’t necessarily a large technical innovation - the basic technology to do this is already there, especially if you’re not running the entire car off solar panels. Stanford University, among numerous other institutions, has shown you can get great results from combing the power of the sun and an automotive. It’s not going to blow anyone’s mind that this is possible.

But I think that’s actually the beauty of it. It’s mundane. It’s cool. It lets people know that solar has arrived, and marks a small step towards solar being known as the go-to for practical application of renewable energy technology.

To add a caveat, there’s always the risk that this reinforces the very dangerous assumption that solar is nifty, trivial, and extraneous, as opposed to something that can do more substantial work. But if the solar industry and Toyota itself can finesse this, the move could just come out by making solar look like what it is - eminently flexible and resourceful, a scalable energy solution.

On the whole it’s marvelous to think about and I can only hope that the rumor is true. And, if Toyota doesn’t bite and what should be a low-cost, high-gain publicity initiative, maybe another company will hear the rumor and decide to pre-empt them.

After eating Toyota’s hybrid dust for years, GM is scraping together a pretty respectable portfolio to prove its commitment to alternate engine technologies and sustainability. The all-electric Chevy Volt is one item in the portfolio (making its maiden car show appearance, so rumors have it, this coming fall), but the real attention-getter is a 12 megawatt solar system to be installed on the roof of their assembly plant in Zaragosa, Spain. My fingers twitched there; it’s hard not type “kilowatt”. A 12 megawatt system is not unimaginable, of course; but it is, frankly, ginormous. The largest installation in the States used to be Google’s 1.3 mw installation in California; just last month, it was ousted by a planned 2.3 mw installation for Atlantic City. Which is still less than one fifth the size of GM’s new darling.

What I find unreal is that all this power, which will be generated by 183,000 square meters of rolled-out panels (Financial Times), will only be enough to supply a quarter of the plant’s power needs. I suppose that’s beside the point, though, which is: Why Spain? Spain has vaulted into a leadership position on solar installations in Europe, due to extremely generous financial incentives. The incentives have been so successful at luring new business that (a): Spain’s solar generation is now almost twenty times what it was at the end of 2005 (from 44mw to 800mw); and (b) the government is probably going to scale them back, and soon. So it’s a good time for GM to be making this move. The company responsible for the installation will be Michigan-based Energy Conversion Devices.

Last week, I sketched a simple picture of the costs involved in installing a 3-kW system in San Francisco. This week, as promised, I’m taking a look at three different financing options. Here we go.

(1) Buy. Obviously, this is the most straightforward option. If you’ve got a enough cash to cover the upfront costs, which in our example are about $20,000, buying the system outright is probably the most hassle-free option out there. Bear in mind, however, there is a time-value to money, and there may be other investments that offer a more attractive return. (Like sending your kids to college…). Seriously though, if you could reliably earn 12 percent on the stock market, you’d be better off putting $5,000 down, taking out a loan with 8 percent interest and pocketing the difference. There are attendant risks to this approach, of course. And even then, some people with ample cash may choose to just buy the system outright and bypass the loan option altogether. I can’t really imagine wealthy Hollywood celebrities, for example, calculating (to the nearest cent) the internal rate of return of a PV system when they could be off riding jet skis and dodging paparazzi in St. Tropez. Anyway, I digress. Bottom line: most of us will either have to borrow or lease.

(2) Borrow. There are a number of different relevant ways to do this, though I’m going to avoid the details as what’s really important here is thinking about the numbers. The first is available through Energy Efficient Mortgages (EEMs). A second option is to borrow directly from your solar manufacturer or installer. Over the past year or so, a number of companies—including Akeena, Sunpower and Sharp—have teamed up with banks to offer equity lines of credit and/or loans with favorable terms for the purchase of PV panels. The third option is to apply for a renewable energy loan from your state or municipal government. Terms are typically as favorable (or more so) than the going market rate. Some governments even offer zero-interest loans for eligible borrowers. To learn about availability and terms, check out our interactive map of solar incentives. (For full details, visit the Database of State Incentives for Renewables and Efficiency website.)

PSE&G, a New Jersey utility, provides a simple (but really handy) loan worksheet (xls) for commercial customers. Residential customers will also find it useful. The spreadsheet provides a quick look at the net present value of a particular PV system, and lets you adjust the discount rate and the rate at which you expect to be able to sell net excess generation (NEG) back to your utility.

(3) Lease. This option is probably the most unique, at least in the realm of renewable energy. And recently it has been catching on. It works like this: you put some money down, typically around $2,000, and agree to a 10-year agreement. The company installs PV panels on your roof and promises to pay for any maintenance, as needed, including the eventual replacement of the inverter. You pay them a monthly rate for the electricity that’s produced by the panels. If it works correctly, everyone wins: the company receives enough money to earn a worth-while rate of return. And you pay a monthly fee that’s lower than what you’d been paying to your utility before the panels were installed. Pretty clever, eh? Awhile ago, I wrote a brief post about SolarCity, a California-based outfit that’s aiming to expand the lease approach. SunEdison is also active on this front.  

In the end, it makes sense that solar manufacturers, and others, should want to ease the burdens of financing. The easier and more attractive the loan options, the more PV panels will be sold. Stay tuned for more in-depth analysis of solar financing in the coming weeks.