Food waste: a new source of electricity


When hearing the phrase “renewable energy”, most of us will think about wind, solar, wave, or geothermal power.

In fact, treating food waste can also be a good way to generate electricity.

Food waste contains many organic components and can be biodegraded. One important way to treat it is anaerobic digestion.

The process breaks down food waste in the absence of oxygen. It can produce biogas as green bioenergy.

Biogas can burn to generate electricity and heat, or can be processed into renewable natural gas and transportation fuels. Moreover, it can reduce electricity prices when compared with wind and solar power.

In a recent study, researchers examined the use of wind power, solar power, and biogas in several countries during 2014-2015. The result indicated that biogas provided an important energy supply.

In the USA, wind power generated 4.1% of electricity, solar power produced 0.2% of electricity, and biogas from food waste generated 0.88% of electricity.

In China, wind power generated 2.8% of electricity, solar power produced 0.18% of electricity, and biogas generated 2.15% of electricity.

In Australia, wind power generated 6% of electricity, solar power produced 1.5% of electricity, and biogas generated 0.57% of electricity.

In Germany, wind power generated 8.7% of electricity, solar power produced 5.3% of electricity, and biogas generated 1.3% of electricity.

In Japan, wind power generated 0.4% of electricity, solar power produced 1.4% of electricity, and biogas generated 1.9% of electricity.

Researchers also compared the cost of electricity in biogas, solar power, and wind power in the above countries. The cost usually includes initial capital, discount rate, cost of continuous operation, fuel, and maintenance.

It showed that biogas had a much lower capital cost than wind power (the USA, Australia, China, and Germany) and solar power (Australia, Germany, and Japan). In addition, biogas had a lower operation and maintenance cost than wind power (Australia, the USA, and Germany).

Researchers suggest that biogas from food waste have lots of advantages, including independence from geography and season, low costs, and stable feedstock.

However, un-sorted food waste may affect operation process, and currently, not all countries have the anaerobic digestion technology to treat food waste. Future work should address these issues.

Copyright © 2018 Knowridge Science Report. All rights reserved.