Finding Renewable Energy in Unusual Places

Kirsten Long

While solar panels, and windmills may be obvious renewable energy tools, there are some unusual places that researchers have found green power sources.

Nanotechnology is being explored as a way to produce renewable energy. One application being looked into is the generation of steam from sunlight. Sunlight that is concentrated on nanoparticles can produce high efficient energy, which can be used to generate steam for running power plants, as well as in solar steam devices that purify water and disinfect dental instruments. Another green application involves increasing the electricity generated by windmills. Carbon nanotubes containing epoxy are helping to make stronger and lighter windmill blades, increasing the amount of electricity produced by each windmill. Nanotechnology is also being used in the generation of electricity from waste heat. Nanotube sheets made of thermocells conduct electricity when the cells are at different temperatures. The sheets can be used to harness waste heat from car exhaust pipes to generate electricity. The nanotube sheets simply wrap around the hot pipes.

We move from the power of nanotechnology, to green algae generating biofuel. Last spring researchers in Japan revealed that the mechanism responsible for oil synthesis in microalgae cells could help (assist) in developing biofuels. The microalgae cells are able to divide quickly with limited amounts of minerals, allowing for them to be harvested faster than land-based biomasses. Harvesting algae can be done any time of year, offering us a stable supply of energy. Not long ago, a new species of marine microalgae, green alga, was discovered by a research team to have a high growth rate and high levels of lipids. The team developed a method to figure out how this species produces oil in its cells. When the cells were incubated with carbon dioxide, over half of the cell weight was carbohydrates. When there was between one and two percent saltwater in the incubation liquid, the amount of carbohydrates decreased and the amount of oil increased. After only seven days, 45 per-cent of the cell weight was oil. This is because an enzyme breaks down the starch observed in the cells of green algae in a saltwater solution. By adding more seawater, the production of starch switches to production of oil. This discovery can help improve the method in which algae is cultivated, thus increasing the amount of biofuel production. The team is continuing to find ways to improve efficiency of cultivation methods in order to increase sustainable oil production.

Also worth mentioning when it comes to unusual renewable energy sources is the fact that biosolar researchers are using green fluorescent protein (or GFP), the goo that makes jellyfish glow, to develop sustainable solar cells. When GFP is paired with light-activating proteins from bacteria, they are able to make a solar cell. These organic solar cells are inexpensive and are created using an environmentally friendly element, making them great in terms of sustainability. The hope is to eventually make a thick paste with the green material, which can be painted onto surfaces to generate electricity.