Popeye Was Right: There’s Energy in Spinach!

November 28, 2016

Using a simple membrane extract from spinach leaves, researchers from the Technion have developed a bio-photo-electro-chemical (BPEC) cell that produces electricity and hydrogen from water using sunlight. The raw material of the device is water, and its products are electric current, hydrogen and oxygen.

The unique combination of a man-made BPEC cell and plant membranes which absorb sunlight and convert it into a flow of electrons highly efficiently, paves the way for the development of new technologies for the creation of clean fuels from renewable sources: water and solar energy.

The BPEC cell developed by the researchers is based on the naturally occurring process of photosynthesis in plants, in which light drives electrons that produce storable chemical energetic molecules that are the fuels of all cells in the animal and plant worlds.

In order to utilize photosynthesis for producing electric current, the researchers added an iron-based compound to the solution. This compound mediates the transfer of electrons from the biological membranes to the electrical circuit, enabling the creation of an electric current in the cell.

The electrical current can also be channeled to form hydrogen gas through the addition of electric power from a small photovoltaic cell that absorbs the excess light. This makes possible the conversion of solar energy into chemical energy that is stored as hydrogen gas formed inside the BPEC cell. This energy can be converted into heat and electricity by burning the hydrogen in the same way hydrocarbon fuels are used.

However, unlike the combustion of hydrocarbon fuels—which emit greenhouse gases (carbon dioxide) into the atmosphere—the product of hydrogen combustion is clean water. The closed cycle begins and ends with water, allowing the conversion and storage of solar energy in hydrogen gas, which could be a clean and sustainable substitute for hydrocarbon fuel.

 

Source: Excerpt of press release by the Technion Israel Institute of Technology