Tag Archives: energy efficiency

More efficient cook stoves for Haiti: In lab with Katee Lask

Lighting a cook stove

Just up the hill at the Lawrence Berkeley National Laboratory (LBNL), a handful of UC Berkeley graduate and undergraduate students congregate in warehouse-like Building 60 each week to cook up two gallons of rice and beans, flavored with salt and garlic to taste. The students aren’t especially hungry for this typical Haitian meal (in fact, they’re probably a bit tired of it at this point)–they’re conducting experiments on cook stove efficiency. Arguably, they are doing some of the most important research currently being carried out at Berkeley, all in a facility that is a far cry from what we usually think of as a high-tech engineering laboratory.

The team is part of the research group of Ashok Gadgil, professor of Civil and Environmental Engineering (CEE) at UC Berkeley. One of his students, Katee Lask, recently gave me a tour of the group’s laboratory and spoke to me about their current efforts toward helping Haitian refugees.

Since the January 2010 earthquake, millions of Haitians have been living in refugee camps, displaced from their homes when the frail buildings collapsed. Critical resources, like charcoal for cooking, are difficult to obtain for a reasonable cost in the camps. Moreover, the cramped nature of the camps means that many kitchens burn charcoal in close proximity, polluting the air and presenting a potential health hazard for the refugees. UC Berkeley and LBNL engineers, including Gadgil and Lask, have stepped in to help develop cleaner and less costly means of cooking food for the refugees.

Gadgil originally became involved with cook stove engineering in 2005, with the goal of assisting war-displaced refugees in Darfur, Sudan. That project culminated in the Berkeley-Darfur Stove, a wood-burning stove with more than 15,000 units deployed to Darfur families by the end of 2010 alone. Later, a modified version of the Berkeley-Darfur Stove was designed for cooking use by families in Ethiopia, where wood is also used as the solid fuel source. As a result of these two projects, when the earthquake hit Haiti, the Berkeley team was uniquely qualified to assist with cook stove issues in the refugee camps.

Tomorrow and Friday: BSR live blogs the BERC Innovation Expo and Energy Symposium

At some point during the last year and a half, you’ve probably found yourself thinking: “I really wish the BSR Blog team would live blog a campus event.” Well, the wait is officially over. Tomorrow, Oct. 20 and Friday, Oct. 21 we’ll be posting live updates from the BERC Innovation Expo and Energy Symposium, an exciting event showcasing cutting-edge energy research from UC Berkeley and beyond. If you can’t make it to the events in person (tickets are selling out fast), join us here on our website from 6 – 9 PM Thursday and 9 AM – 6 PM Friday, and we’ll make sure that you don’t miss a thing!

Reaching for the sun

Most of the time, doing something 28% efficiently is nothing to be proud of. But in photovoltaics, it is good enough to set a new world efficiency record—and earn the company that made the record-setting devices millions of dollars in venture capital.

In this case, the lucky company is Alta Devices, which until recently held a low profile in the crowded solar industry. For the last few years, Alta has been quietly developing a novel process for cheaply manufacturing ultra-efficient solar cells. Their hard work appears to be paying off, because last month the company reported that they can make cells that are 28.2% efficient at converting solar energy into electricity. This beats the previous record by more than one percent, a wide margin by the solar industry’s standards.

Alta’s solar cells are made of a semiconducting material called gallium arsenide. Because this is a relatively expensive material, most solar companies use cheaper, less efficient alternatives such as silicon. But Alta came up with a transfer process that allows them to lay gallium arsenide layers that are only one micron thick (about 100 times thinner than a sheet of paper) on each cell.  The thin layers don’t use up much material so they don’t cost very much, but they still generate as much electricity as a thicker layer would.  The company’s goal is to generate electricity at a cost of under 50 cents per watt, which is about twice as cost-effective as the current state-of-the-art.

Coming soon to Berkeley: Energy efficient electronics using nanotechnology

To date, nanotechnology has generated lots of excitement in the scientific community, but it hasn’t exactly brought about transformative changes in the life of the average person. In an effort turn that corner, UC Berkeley recently established the Center for Energy Efficient Electronics Science (E3S), where researchers will work to develop a new generation of nanotechnology-based computer chips that require so little energy that they may never need to be plugged in or recharged. The applications of this research go far beyond improving your laptop’s battery life (important as that might be) and into the realm of making entirely new technologies viable, like biosensors and ubiquitous wireless networks. E3S is led by EECS professor Eli Yablonovitch, whose long list of honors includes his very own Wikipedia entry.