Harry Atwater is working on the forefront of alternative energy technologies. From his research in solar fuels to his innovation in photovoltaics, Atwater’s work addresses the energy crisis and strives to provide a more secure, sustainable future.
Currently, Atwater is the Howard Hughes Professor of Applied Physics and Materials Science at the California Institute of Technology (Caltech) and Director of the Joint Center for Artificial Photosynthesis (JCAP). You can catch Atwater at the fifth international ECS Electrochemical Energy Summit, taking place October 12th through the 14th 2015 in Phoenix, AZ.
Five Questions for Harry Atwater
“These are pretty life-changing consequences, how we produce and use energy.”
What brought you to renewable energy research?
That stems from my early experiences as a school student growing up in Pennsylvania during the mid- and late-1970s. That was the time of the first so-called “energy crisis” in the United States when the Arab countries formed a cartel that embargoed energy exports. There were oil shortages and I recall very vividly as a grade school and high school student having to wait for odd/even gas rationing in order to refuel our cars. I also recall an episode where our school was shut down for a period during the month of January. I thought to myself, “These are pretty life-changing consequences; how we produce and use energy. If I ever have a chance to do something about it, I’ll dedicate some effort to that.”
How has the solar industry changed over the years?
When you look at solar energy and energy as a whole, you have to look at the overall evolution of technology and the demand cycle. While I was a graduate student at MIT, we were living in a period of very inexpensive fossil energy. In fact, we’re sort of in a period like that right now. Nonetheless, many of the basic needs for renewable energy were articulated during that first energy crisis. In particular, the first development of a photovoltaics technology, crystalline silicon wafer-based solar cell technology, that is now the ubiquitous manufacturing scale technology for solar photovoltaics today. Today we have a solar industry that’s really become a serious industry. It’s no longer the niche, boutique industry that I recall from the mid- to late-90s. It’s become the largest optical electronic industry in the world.
Is solar a practical form of energy?
What we saw as a possibility starting in the early- to mid-2000s was that silicon technology was really going to be the first wave of large-scale manufactured photovoltaics, but that there was so much greater opportunity. The greater opportunities are always going to lie at higher efficiencies because what we’ve seen over the last decade is that it’s become a very mature industry in the sense that the costs have dropped dramatically that the average cost of electricity in the United States for solar right now is $0.05/kWh, which is a remarkable number considering where we started.
What kind of research are you working on right now?
So in the lab right now at Caltech and with the others that we work with, we’re looking toward even higher efficiencies. We’re looking to go to technologies that split the solar spectrum into their different spectral bands. As to more efficiently convert the sun’s energy into electricity without so-called thermalization losses.
What are some of the limitations of solar and how do we resolve them?
Solar cannot inherently store the electricity that’s generated in the solar photovoltaic cell, you have to use it at the time that it’s generated. But it’s predictably intermittent because of the night time, but unpredictably intermittent because of the change of local weather patterns. However, that really has driven the chemical scientists to get into the game to really think about ways that we can generate directly chemical fuels from sunlight. I think that’s a very compelling direction to go because the intermittency may limit the degree to which solar photovoltaics could be incorporated into the grid, but if we could really make storable solar energy then there would be equivalence between the fuels that we use today to power our transportation needs and heat our homes and so forth. That’s were JCAP comes in. JCAP is really dedicated to the solar fuels hub, building integrated solar fuels generators, and focusing on building prototypes that generate renewable solar fuels.