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.
This is the first post in a series on zero-net energy homes. Over the course of the series I will be covering all aspects of this topic, from the technology and knowledge available today, to the changes needed in technology, building codes, trade skills, design approaches, and will to achieve the goal of all new homes eventually being zero net energy.
Definitions and feasibility
What is a “zero-net energy home?” Zero net energy homes generate as much energy as they use. Energy used = Energy Generated. The experience of thousands of “off the grid” home owners and those bleeding edge homeowners with big solar panel installations on their roofs show that zero-net energy homes are technically feasible today. For example, see this article on Amory Lovins’ home and office in Snowmass, CO.
We know how to build them. Unfortunately, for most homeowners, they are too expensive, because the energy generation side of the equation is too costly. There are three ways to address this problem.
Reduce the cost of home-based energy generation, typically either solar or wind. That depends on technological improvements and manufacturing efficiencies by the solar panel companies, and they are busily doing their best to address this situation.
Change the cost basis for comparison – energy generation is expensive compared to the cost of electricity from coal-fired plants, but a carbon tax on those plants would automatically make solar more competitive (and raise the cost of energy for all of us).
Make the demand side of the equation – energy used – smaller. Reducing the energy used by half cuts the energy required by half, which cuts the cost by half. And typically reducing energy use has numerous other cost benefits, and often performance benefits as well.
Over the course of this series of articles, I’ll be looking at how both sides of the equation can be reduced, but the particular focus will be on getting the demand side down.
Privation is not the solution
One way to reduce the energy use of the home is simply to do less – for example, you can save a lot of hot water if you simply stop showering every other day. Other techniques are leave the heater off when it’s cold, or the AC off when it’s hot. There’s also sitting in the dark – lighting accounts for about 15% of home energy use. Strangely, most homeowners in the U.S. are unwilling to reduce their energy demand by cutting “services” in this way.
Therefore, we have to find ways to reduce energy usage while not cutting the “services” the home provides. We all need our showers, our lights, and our comfortable temperatures. The good news is that by making small changes in how homes are designed and built, typically at a very small increment to the cost of the home overall, we can build houses that use one half the energy or less, and often at a higher level of comfort and “service” than standard-built homes.
As we will see over the next few articles, we already have all the technology, and some people have the experience, to build “zero-net energy ready” houses cost effectively.
On the energy generation side, although there’s currently a premium to get to zero-net energy, over the next ten years this premium will go to zero. In fact, looking farther ahead, it may become cost-effective to get to positive-net energy – where the house is generating more energy than it needs! Such a change has world-changing implications – but we’ll cover that later in the series.
Zero-net energy homes is a huge topic, and some of the areas we’ll be covering in future posts are:
Home energy storage
Zero-net energy for existing homes
Zero-net energy and LEED
Practical steps for finding a zero-net energy home builder
Examples of zero-net energy homes
Achieving a zero-net energy home cost-effectively
How the cost-benefit equation on zero-net energy homes is likely to change over the next five and ten years
As I get started on this series, I’d love to hear your comments and thoughts on what I’ve presented here, as well as other topics I should cover in future posts.
Oh Snap! Now some German scientists have (in effect) taken a swing at Stanford professor Mark Z. Jacobson, who concluded in a recent paper that biofuels are a bad policy direction (see summary post here).
Their key discovery is that by reforesting land that has been “degraded by human use in historical times”, they found:
… the global energy demand projected by the International Energy Agency in the Reference Scenario for the year 2030 could be provided sustainably and economically primarily from lignocellulosic biomass grown on areas which have been degraded by human activities in historical times.
The Rocky Mountain Institute’s Andrew Demaria blogged a few weeks ago about “smart garages” that combine smart cars, a smart home network, and much smarter utilities into a synergistic system that optimizes power usage. After describing a “day in the life” of a smart garage:
Given the utility is experiencing a peak load period, it asks my house if it can use the spare power in the car’s battery and send that electricity elsewhere in the grid. What’s more, it will pay me for that power. Since I like being paid, I have already programmed the system to accept such requests.
The article then goes on to list the highlights of a recent Smart Garages conference organized by RMI. Attendees included representatives from auto manufacturers GM, Ford, and Nissan, utilities PG&E and Duke Energy, and consumer-focused companies Walmart and P&G.
Integrative design like smart garages requires all these organizations to work effectively together, based on official or de-facto standards. Although the cost of making such a transition will be hundreds of billions of dollars, the associated business opportunities, especially for those companies who can help tie all these disparate parts together, are commensurately huge.
I plan to do an in-depth post or series on fuel cells soon, because there is so much breakthrough work going on in this research area. Fuel cells are interesting on so many fronts – for example, they’re probably the best way to use the hydrogen generated by Daniel Nocera’s new hydrogen splitting method, announced in mid-August. And just since August, researchers have announced big improvements or cost reductions in every component of the fuel cell – membrane, catalyst, and electrodes.
This latest story from Technology Review covers a new membrane improvement for methanol fuel cells. As the article points out, methanol fuel cells have some key benefits compared to hydrogen cells, in particular that methanol is a liquid at normal temperatures, but they also have technical challenges. Paula Hammond and her team are addressing one of these:
In her lab at MIT, chemical-engineering professor Paula Hammond pinches a sliver of what looks like thick Saran wrap between tweezers. Though it appears unremarkable, this polymer membrane can significantly increase the power output of a methanol fuel cell, which could make that technology suitable as a lighter, longer-lasting, and more environmentally friendly alternative to batteries in consumer electronics such as cell phones and laptops.
Do you have questions about fuel cells that you’d like me to find answers to as I research my upcoming series? Let me know in the comments.
Moore’s Law depended (and still depends) on a constant flow of breakthrough technologies, processes, scale, and designs. You can’t necessarily predict how Moore’s Law will continue to hold two years from now, or five years from now, but you can be confident that through some combination of technologies, processes, and designs, the price/performance of IT will continue to decline at an exponential rate.
The top five green energy stories of 2008 give an indication that the same types of forces are at play in the green energy world. Numbers 1, 2, and 3 each represent a potential 10x reduction in the cost of the most expensive part of a particular energy flow. For number 4, Gore used the bully pulpit of a Nobel Prize and Oscar (and, oh yeah, he was nearly president) in a most constructive way. And number 5 illustrates that green energy technologies are on a growth rate of doubling about every 18 months.
Did these stories excite you as much as they did me? Were there other green energy stories in August that you feel are more important?
The short answer is: while 100% is probably unrealistic, it’s not unreasonable to expect to be able to get pretty close to that number (say, in the 50-90% range) in that timeframe, and it is very likely that it makes a LOT of sense economically.
As you’ll notice Jerome has made somewhat different assumptions from mine, particular in regard to the total electricity demand. As I mentioned, I plan to drill down more into my analysis and take it from the “zero-order” to “first-order”. I’ll also revisit my assumptions to make sure we’re comparing apples to apples.
Some researchers at Melbourne’s Monash University in Australia have made yet another breakthrough related to making fuel cells more feasible for general purpose use. Their breakthrough is related to a new cathode design, made with a much cheaper material than the typical platinum. The result is an order of magnitude reduction in the materials cost for the fuel cell.
Professor Maria Forsythe and her colleagues used a conducting polymer (a special plastic that conducts electricity) called poly(3,4-ethlenedioxythiphene), or PEDOT for the cathode, instead of platinum. The amount of platinum required for a passenger car fuel cell costs $3500 to $4000, and accounts for the major part of the cost of the fuel cell. Using PEDOT for the cathode reduces the cost to a few hundred dollars.
Forsyth says the cathode could also be used in zinc air batteries, which are under development for storing energy in cars.
It’s been a great week for energy! In separate announcements, scientists at MIT, a university in Spain, and at an energy startup in Texas made some amazing claims that to me indicate that what we think we know about alternative energy and energy efficiency, we don’t know.
At MIT, Dr. Daniel Nocera announced a new, much lower energy process for separating water into hydrogen and oxygen, using new catalysts developed in his labs. This discovery, if it can be successfully commercialized, represents perhaps the best currently known way to store solar energy for when the sun’s not shining. The idea is that when the sun is shining, electricity generated by solar photovoltaic cells would be used to generate hydrogen, which would then be used later in a fuel cell to generate electricity when it’s needed, such as to drive your electric car, or to heat the water for your shower in the morning.
Using sunlight to split water, storing solar energy in the form of hydrogen, hasn’t been practical because the reaction required too much energy, and suitable catalysts were too expensive or used extremely rare materials. Nocera’s catalyst clears the way for cheap and abundant water-splitting technologies.
In an unrelated story, scientists at Universidad Complutense de Madrid in Spain announced a new electrolyte for use in solid oxide fuel cells which could significantly improve their practicality. Until now,
the high temperatures required for efficient operation make solid-oxide fuel cells expensive and limit their applications. The low-temperature electrolyte reported by the Spanish researchers could be a “tremendous improvement” for solid-oxide fuel cells, says Eric Wachsman, director of the Florida Institute for Sustainable Energy, at the University of Florida.
Finally, EEStor, a hugely-funded battery startup in Texas announced a major milestone in their efforts to create a new battery technology that “will have more than three times the energy density of the top lithium-ion batteries today and … the ability to recharge in less than five minutes.” There is a lot of skepticism about EEStor’s claims in the scientific community, in part because they have not yet demonstrated their technology to outside reviewers. But if their technology is real, and a number of top-line venture capital firms are betting that it is, the accepted wisdom about batteries will have a sea change. There’s even a car company that’s committed to using the new battery in the near term:
Toronto-based ZENN Motor, an EEStor investor and customer, says that it’s developing an EESU-powered car with a top speed of 80 miles per hour and a 250-mile range. It hopes to launch the vehicle, which the company says will be inexpensive, in the fall of 2009.
Hopefully we’ll be hearing more concrete information soon. Dick Weir, founder and president of EEStor, says they’ll be coming out with more information about their progress and technology on a “more rapid basis.”
That makes three major announcements about energy storage in one week, any one of which, if it’s successfully commercialized, changes the economics and practicality of alternative energy. Given that alternative energy and energy efficiency are already cost-effective and “ready for prime time,” these changes could literally deliver the very low-cost energy that nuclear power advocates promised 50 years ago. But this time it will be truly clean.