Solar power under the stars
Today’s best photovoltaic cells can produce electricity only when the sun is up. But engineers at Stanford University are developing a solar cell that can also generate power at night. Writing in the journal Applied Physics Letters, the researchers say their solar collector incorporates a thermoelectric generator that harvests electricity from the temperature difference between the PV cell and its ambient surroundings. In other words, the device makes use of the heat leaking from Earth back into space – an energy flow on the same order of magnitude as incoming solar radiation. The scientists report that their process is simple, inexpensive and “can be used as a continuous renewable power source for both day- and nighttime in off-grid locations.”
Lithium goes green-ish
As green mobility grows, industry will have to find better ways to mine lithium, the key element in today’s rechargeable batteries. Right now, mining it is a nasty, dirty business, centred in China, Australia and Chile. The good news: the U.S. Department of Energy’s Pacific Northwest National Laboratory (PNNL) is testing a process that uses magnetic nanoparticles to capture lithium, and other rare materials, from briny wastewater produced in mining, fracking and geothermal energy projects. With lithium demand expected to grow 15-fold by 2050, the United States wants to bring lithium processing back home. Jian Liu, a senior research engineer at PNNL, says his team’s process could produce 34,000 tons of lithium per year in the United States alone, at lower costs than miners currently charge. Says Liu, “We believe that this thing can be big.”
Good moos for the planet
Ben & Jerry’s, the socially conscious ice cream brand now owned by consumer-products giant Unilever, has always stood for peace and love. Now it’s targeting climate change. Through “Project Mootopia,” it aims to cut greenhouse gas emissions in half on 15 dairy farms by the end of 2024. How do you keep carbon down on the farm? Ben & Jerry’s three-point plan includes reducing the methane produced by cow burps through higher-quality forage menus, using methane-reduction technologies to reduce the carbon footprint of cow manure, and growing more grass and other feed crops to maintain healthy soils, increase carbon sequestration and promote biodiversity. If those pilot initiatives prove effective, the company plans to expand these efforts across its entire global dairy supply chain – which produces more than 50% of the company’s total carbon emissions.
No hiding place for poachers
Canada’s high-profile electronics company MDA (formerly MacDonald, Dettwiler & Associates) built the country’s first Earth-orbiting satellite. Now it’s using satellite technologies to track poachers on the high seas for Canada’s Department of Fisheries and Oceans. At a conference in Australia in May, MDA and two partners unveiled their process for tracking “dark” ships illegally fishing for southern bluefin tuna. Dark ships travel without broadcasting the required automatic information system (AIS) data that normally identify vessels’ course, speed and destination. MDA’s RADARSAT-2 surveillance satellite can identify dark vessels across thousands of square kilometres of ocean and generate the real-time data governments need to find and track offenders.
Gucci backs lab-grown leather
Leather may have fallen out of fashion in the movements against climate change and animal cruelty, but the US$400-billion industry is fighting back. In May, California-based VitroLabs Inc. raised US$39 million to develop lab-grown leather through tissue engineering (no dead animals required). The firm’s backers include a venture-capital firm focusing on cellular agriculture, vegan evangelist Leonardo DiCaprio and French luxury brand Kering, whose holdings include Gucci and Yves Saint Laurent. VitroLabs will open a pilot plant next year, with Kering’s fashion experts helping with testing, tanning and finishing. For Kering, it’s not just about fashion, a spokesperson said: “Without breakthrough solutions, we won’t be able to reach our sustainability targets.”
Making electricity out of compressed air
To provide more renewable power during peak-demand periods, China has just inaugurated its first commercial compressed-air energy storage plant. State-owned China Huaneng Group says the 60-megawatt plant is the largest plant of its type built in the world since 1991. In compressed-air energy storage, electricity produced at night (when demand is low) pumps air into airtight underground caverns. When demand rises the next day, the plant releases the air, which spins a turbine to produce new electricity. (A Toronto-based company is developing similar technology for use in Canada and around the world. Read up on Hydrostor in our Future 50 coverage.)
