The LED City program was started by Cree, a US-based manufacturer of LED components in 2007. They have a number of cities around the world already signed up for the program, including Raleigh, NC; Ann Arbor, MI, Austin, TX; Toronto, Ontario; Tianjin, China, and Torraca, Italy.

According to the report, the US generates over a billion tons of cow manure annually, most of which is left in storage areas to decompose naturally. That decomposition process produces air pollution and greenhouse gases (we reported earlier that an Argentinian study had concluded as much as 30% of that country’s greenhouse gas emissions could be coming from their cattle).

Anaerobic Digestion

Through the process of anaerobic digestion the manure can be converted into methane-rich biogas, and a nearly odorless sludge which can be used as a fertilizer. The biogas can be used as-is for heating homes or cooking; it can also be converted to natural gas by a scrubbing process that removes the carbon dioxide and hydrogen sulfide and then used where CNG would be used today (e.g. in powering vehicles).

Cow Power
The UT report suggests that using this biogas to generate electricity could help reduce the amount of power generated from coal fired power stations, and in doing so help reduce the carbon emissions. The results of the study suggest that using this biogas could result in a reduction of between 44 and 173 tons (40 to 157 tonnes) of carbon dioxide emissions.

The real question I was left with after reading the report though was whether electricity generation is the best use of this biogas. Are any of the other possible uses better at reducing carbon emissions?

[Via Earth2Tech]