Urban food waste can be a source of renewable energy

BANGLADESH is still way behind in converting food wastes into a valuable and renewable source of energy.

When the waste disposal systems especially in cities and towns are not smart and effective, converting food wastes into biogas can be useful in both ways: removal and profitable use of the wastes.

According to a recent report, Dhaka’s fresh markets generate an estimated 5,000 tons of organic matter every day, but these wastes are thrown away, when they can be put to good use for renewable sources of energy.

These wastes are indeed investment opportunities in converting food waste into energy.

If the technology of bio-digesters that generate biogas from the urban food waste is initiated at a large-scale, as an energy-starved country Bangladesh will be considerably benefitted from it.

However, agricultural wastes, manure, municipal waste, plant material, sewage, green waste and food waste can be converted into biogas, which is a mixture of gases from raw materials, using the bio-digester technology.

The Dhaka North City Corporation (DNCC) and Dhaka South City Corporation (DSCC) alone produce 2.7 to 2.9 million tons of waste annually of which about 70% of the waste is food-related organic waste.

It is essential now to promote the recycling of food-related waste, which comprises a significant portion of municipal waste.

Another option for urban food waste is black soldier flies (Hermetia illucens).

Black soldier fly larvae feed voraciously on various types of organic waste and reduce the initial weight of the organic waste by about 50% in a shorter period than conventional composting.

Black soldier fly larvae have been proven to convert organic waste into high-quality nutrients for pet foods, fish and poultry feeds, residue fertiliser, and pet food.

These flies can be grown on various types of organic waste, including food and vegetable market waste.

The production of insect-based animal feed can contribute to a more resilient and sustainable food system in Dhaka.

At some places of the country organic manure is being turned into biogas by private initiative for personal use, but even this has yet to become popular.