I have been discovering and joining a few interesting online communities focused on energy and sustainability issues. While it’s hard to keep up on everything that’s going on, they seem like a good source of like-minded folks with whom to discuss your ideas.
One of these is the Energy Collective. One of their features is that they aggregate selected posts from a number of blogs in the green energy space. The posts selected are usually meaty, and there are typically quite a few comments on each post through the Energy Collective.
Interesting note flying around the blogosphere yesterday (see here, here, and here, amongst many websites featuring the news) about a research project done at Berkeley. It found that, based on material cost and availability, solar photovoltaics made with iron pyrites (aka Fool’s Gold) are more likely to solve our energy crisis than PV made with silicon or CIGS thinfilms. This is due to both the cost of the raw materials and their availability – both crystalline silicon and the CIGS precursors are relatively expensive and relatively rare. Iron pyrite and its precursors are among the most common elements on earth, in contrast.
What we’ve found is that some leading thin films may be difficult to scale as high as global electricity consumption… if our objective is to supply the majority of electricity in this way, we must quickly consider alternative materials that are Earth-abundant, non-toxic and cheap. These are the materials that can get us to our goals more rapidly.
The paper noted that PV cells made with iron pyrite are not as efficient as those made with silicon, but here’s where it gets interesting. I did a Google search yesterday to find out just how efficient those iron pyrite solar cells are – and I can’t find them. There are a handful of papers about iron pyrite solar cells, but none that indicate it’s anywhere near being ready to compete even on the low-efficiency end. (E.g., see here, in a paper from 2000.)
So, that may mean I’m just not any good at searching on Google, and be that as it may. The other side of the coin is that this report lines up with what I’ve [intlink id=”119″ type=”post”]been saying since October[/intlink] – it’s not about the efficiency of the cells, it’s about the [intlink id=”194″ type=”post”]price/performance[/intlink]. We have plenty of surface area on which to put solar cells, even if they aren’t very efficient. What we don’t have is lots of extra money to pay for them – so low-efficiency cells that have a good price performance ratio – $1-2/kw or $0.10-0.30/kwh – are what we’re looking for.
(And of course, we need to be a lot more efficient in our energy usage, and be able to store that good sun power we’ve generated.)
In any case, I’m now looking forward to hearing about iron pyrite-based solar cells – if you know of any post-2000 research on this topic, definitely let me know!
According to John Lushetsky, program manager of the U.S., it’s a very big project:
To go from the 1 gigawatt of generation capacity that we have now [in the United States] to the 170 to 200 gigawatts called for by 2030 amounts to a 26 percent compounded annual growth rate over the next 20 years. That’s a higher sustained growth rate than any industry has ever been asked to do before
That 26% growth rate is very high, but there is hope. The semiconductor and IT industries had a similar growth rate over a similar period. In fact, measured using a different metric – price/performance – the semiconductor industry actually grew a lot faster. That’s one reason I like to focus on [intlink id=”189″ type=”post”]price/performance with solar energy[/intlink] – if that metric continually drops, then it’s feasible for alternative energy sources to replace conventional sources. Just as in the IT industry, [intlink id=”66″ type=”post”]the driver for growth in solar is going to be cost parity[/intlink]. That’s why the Google Foundation’s program, for example, is RE < C (“renewable energy costs less than coal“) instead of something like “200 GW by 2030”.
Combining dropping solar power costs with increasing energy efficiency gets you to the goal fastest, of course. Getting efficient is already cheaper than buying energy in a lot of cases. (We need a whole other set of posts to discuss the barriers to getting efficient – it’s cheap, cost-effective, and profitable but still challenging.)
Nabih Tahan, who spoke two weeks ago at a BuildItGreen event on the passive house concept, just told me about Passive House California. They are “a group of building professionals from the San Francisco Bay Area working together to increase public and media awareness of Passive House.”
You can check their website for more information, including their meeting this coming Sunday in Berkeley:
Yesterday the New York Times published an interview (including some of the original audio) with our new Energy Secretary, Steven Chu. Among other comments, he said that to address the climate emergency, we need “Nobel-level breakthroughs” in several key areas – batteries, biofuels, and solar photovoltaics.” As an illustration, he pointed out:
The photovoltaics we have today, … without subsidy, and without even the additional cost of storage, it’s about a factor of five higher than electricity generation by gas or coal. Suppose someone comes along and invents a way of getting … solar photovoltaics at one fifth the cost, so you don’t even think about subsidies anymore. You just slap it everywhere… That, in my opinion, would take something, which I would say, is a bit of a breakthrough.”
There’s no arguing with that idea – if solar PV were five times cheaper, no one would need complicated “payback period” models to justify installing it. (Luckily, we do have those models, and so some people are taking the plunge.)
Of course, this is just the story of how technologies advance – it’s very familiar from the rise of semiconductors. A technology needs an ever-expanding “feedstock” of innovations, discoveries, and breakthroughs to grow at an exponential rate. In semiconductors, the history of technologies such as FET, MOS, CMOS, new clean room techniques, different types of lithography, and many other innovations each offered ever decreasing feature size and lower cost. This parade of innovations combined to ensure that just when one technology was reaching its limit of compactness, another newer and more efficient technology would be there to take its place. When the new one ran out of steam the cycle would repeat. (And several of those innovations resulted in Nobels.)
One example of the “old thinking” on PV is the projections about its availability and cost. Many of these projections assume a linear improvement in price/performance. To help save the world, the price/performance of solar electricity and batteries and efficiency and fuel cells must come down faster than the typical, linear projections – just as it did for semiconductors.
Luckily, despite a current dip in investment and research levels due to the economy, this is happening in the solar photovoltaics domain. [intlink id=”210″ type=”post”]New[/intlink] [intlink id=”218″ type=”post”]discoveries[/intlink], new manufacturing methods, and [intlink id=”66″ type=”post”]new thinking[/intlink] will continue to drive the price down. With luck, Chu’s support from his bully pulpit in the DoE can accelerate this process.
Hat tip to Watthead for turning me on to this interview.
In honor of this blog’s six month anniversary, I’m going to relink to some of my favorite posts from the past:
[intlink id=”5″ type=”post”]My first post, on fuel cell and battery innovations[/intlink]
[intlink id=”119″ type=”post”]Why I am optimistic about our energy and climate future[/intlink]
[intlink id=”126″ type=”post”]Some reasons my optimism is tempered (a follow up to the post above)[/intlink]
[intlink id=”329″ type=”post”]My predictions for 2018 (ten years in the future)[/intlink]
Also, as regular readers know, I’ve been presenting a series of posts on zero net energy homes. I’ve recently added a new plug-in for the blog that makes it easy for you to find these series, and I’ve put the link to the series over on the right hand column (and right here).
The week I started this blog in August 2008, there were [intlink id=”5″ type=”post” target=”_blank”]three major fuel-cell related discoveries[/intlink] making the rounds in the science magazines. Since then, there have been [intlink id=”7″ type=”post” target=”_blank”]new announcements every week[/intlink] of an [intlink id=”229″ type=”post” target=”_blank”]improved catalyst or membrane or electrolyte[/intlink]. As these discoveries mature into real products and enter the market, the option of using fuel cells for energy storage, both for homes as well as vehicles, will become more and more cost-effective.
Energy storage is potentially a big part of the zero-net energy house picture, and is certainly critical for the hydrogen automobile transition. I thought I’d highlight a few recent discoveries and advances in the world of fuel cells, the “energy storage of the future.”
“Fuel cells haven’t been commercialized for larger-scale applications because platinum is too expensive,” says Liming Dai, a materials-engineering professor at the University of Dayton, in Ohio, who led the work. “For electrodes, you need a cheaper material that still has a high performance.”
The new catalyst, developed by researchers at Brookhaven National Laboratory, breaks the carbon bonds without high voltages, efficiently releasing enough electrons to produce electrical currents 100 times higher than those produced with other catalysts.
Now researchers in China have developed a fuel cell that uses a new membrane material to operate in alkaline conditions, eliminating the need for an expensive catalyst. The power output of the new prototype, which uses nickel as a catalyst, is still relatively low, but it provides a first demonstration of a potentially much less expensive fuel cell.
Solid-oxide fuel cells are promising for next-generation power plants because they are more efficient than conventional generators, such as steam turbines, and they can use a greater variety of fuels than other fuel cells. They can generate electricity with gasoline, diesel, natural gas, and hydrogen, among other fuels. But the high temperatures required for efficient operation make solid-oxide fuel cells expensive and limit their applications.
Home-generated energy is sustainable, non-polluting, and carbon-free. As the price of energy generation continues to drop, it’s possible to imagine [intlink id=”329″ type=”post” target=”_blank”]the nation’s homes becoming the nation’s power plant[/intlink]. But that can’t happen until we have effective home-based energy storage.
I read Technology Review for the latest innovations and breakthroughs in fuel cell technology, transparent solar cells, exotic new batteries and things like that. But there are tons of much lower tech innovations happening all the time. I happened to meet a guy the other night who’s working on a new startup related to building construction.
They’ve developed a new structural component – basically a really strong sheet of plywood – and some connectors, and they think based on their current testing results that they can build houses for 70% of the cost of regular 2×4 stud construction, much faster. They have almost no waste on the job site, and the waste in their factory is all reused. The system is fairly green as well – the feedstock for their plywood is bamboo, one of the best plants for taking up CO2 – and they use non-toxic glues and finishes. And their construction method will work very well for [intlink id=”393″ type=”post”]passive houses[/intlink] as [intlink id=”368″ type=”post” target=”_blank”]discussed elsewhere[/intlink] on “Keeping The Lights On”.
But just like the fuel cell breakthroughs, these low-tech innovations have a tough road to travel to success. For a new building process, you have to convince builders that it’s a better alternative, and that they’ll make more money faster. You also have to certify that the houses will stand up in an earthquake, weather a big storm (or ten of them, over the years), and do all the normal things that houses do in their lifetime. You can be sure that other innovators are coming up with competitive building technologies, all trying to accomplish the same thing as you – displace the old way. So not only do you have to deal with differentiation and other competitive marketing activities, but this also means the air around the head of your prospects is blue with pitches from every direction about “revolutionizing the industry” and “lower cost, faster” and “extremely green.”
If you accomplish all those things, and get a good competitive position, then you have to actually make the new materials and all the fittings, making sure you can address the trickier needs of real houses – which are not just square walls and right angle corners.
I think the new plywood-based approach I saw can address all these issues, but my point is that just because it’s good, it’s still going to be a difficult journey. That’s true of any new innovation.
I hope to do an interview in March with the “plywood people” and put it up on the blog, and I’ll be asking them how they plan to address all these issues as they ramp up. It should be interesting to watch them and other innovations in the building trades, especially in this time of massive investment in green building and energy efficiency.
Last night BuildItGreen’s South Bay Professional Guild hosted Nabih Tahan, a Berkeley-based architect who was recently featured in a New York Times article on passive houses. Nabih discussed the passive house concept and how it is being applied in Germany and the rest of Europe, as well as his experience building Low Energy Houses (Niedrigenergiehaus – the generation of homes before the passive houses) in Austria and remodeling his conventional house in the Berkeley flatlands into a passive house.
The term “passive house” reflects the concept that these houses do not have heaters to provide warmth. Instead, they “passively” recover heat from all the other activities in the home – such as cooking, lighting, and even human activity. To enable this, a passive house is highly insulated, with an airtight building envelope, so that no heat can escape. To keep the air quality high, passive houses use “heat recovery ventilators” or “energy recovery ventilators” with air-to-air heat exchangers to constantly replace the old inside air with new outside air, while keeping the heat from the old air inside.
Passive houses typically use about 80% less energy for heating and cooling than conventionally-built houses.
Tahan’s talk covered a huge amount of ground. Some of the high points included:
A description, with a number of photos and a video, of the current German and Austrian technologies for building houses and multi-family residences. These homes are built in factories, by automated, computer-controlled machines, and assembled in a few days on site. Because all the pieces are designed to high tolerances, the building sites are very quiet – if you hear a power saw on one of these sites, you know someone made a mistake.
He showed a picture of “model home mall” in Austria (here’s something similar in Germany – in German), where more than 40 of these pre-built home builders have built 80 model homes that you can tour. The homes range in size and style from modest single family houses to large mini-mansions, to apartment buildings.
I asked what one change in the U.S. would make it easier to build passive houses here. He said better windows and doors. Insulated and well-sealed windows and doors, often with triple-glazing and special coatings on the glass, comprise a key component of passive houses in terms of keeping the building envelope airtight. There are many manufacturers of these components in Germany and the rest of Europe, but none to very few in the States. In fact, Tahan is currently in discussions with investors on starting a factory to build these components, in partnership with an Austrian company.
For his Berkeley house, he decided to work with a U.S. supplier, Sierra Pacific, to demonstrate that the passive house standard is possible in the California climate with local products. In any case, buying the windows in Austria would have cost less than buying them here, but the cost of shipping would have made the Austrian windows more expensive.
In building a passive house, airtightness is as important as the insulation – they work hand in hand. And it’s the most difficult part, especially in the United States where buildings are not constructed by computer-controlled machines.
In Europe, building a passive house costs 4-5% more than conventional construction, but it saves 80% of the energy. Currently it’s a somewhat bigger premium to build a passive house in the States, due to lack of suppliers and know-how.
The passive house concept and approach is clearly a component of a zero-net energy home program. Reducing the amount of energy a home uses means it’s a lot easier and cheaper to generate that energy onsite. Architects like Tahan will be a key enabler of getting to the [intlink id=”329″ type=”post”]2018 goal of 100% zero net energy homes in California[/intlink].
This was an excellent talk, and I’m looking forward to hearing more from Nabih Tahan, and attending more BuildItGreen functions. If they’re all at this level, they’ll be a great resource for getting California to the goal of 100% zero net energy new houses by 2018.
Update (2/13/09): Nabih tells me that the Passive House California Group has just set up their website, where you can read about their next group meeting and other topics.
Liability – this is one of the biggest issues at the front of mind for builders and architects – they have to guarantee their buildings, and that makes them very wary of new technologies. One big challenge for green building will be coming up with ways to break through that barrier (the other alternative, of course, is to wait long enough that the new technologies prove themselves – but even this needs to be optimized). For example, perhaps the government could help take on some of the liability to reduce the risk for architects and builders trying to do the right thing.
Perception – Silicon Valley, as one of the attendees pointed out, is way ahead of the rest of the nation in terms of our perception that “green is just an obvious thing to do.” The general idea that green is more expensive or that it requires privation is much more prevalent. So a big challenge for the green movement is to change that perception, which is a combination of both marketing (the next topic) as well as changes in the way green is delivered. Simple changes (see my CSA “box of veggies” post, for example) can make a huge difference in perceptions.
Marketing – half of us at the salon were high tech marketers. Green technology is a classic high-tech marketing problem. We’re facing a “chasm” that we need to get across. There’s a technology adoption lifecycle in green building just as there is in new IT technologies. Of course, that’s one of the things that we here in Silicon Valley are pretty good at (we wrote the book on it :-). So one good set of steps to move forward will be to articulate a “Crossing the Chasm” kind of analysis of green, and figure out where our “beackheads” are, and how to get a “tornado” going.
Most of the news about green energy and climate change focuses on the big multi-million dollar technical projects, scientific breakthroughs, and “parts per million.” But as we discovered at our salon, there is a lot of “ground-level” work that has to be done at the same time – whether it’s to remove obstacles for builders to build green, or to help consumers understand they can save money and get better services and, oh by the way, save a lot of energy at the same time.