Poo power plan for generator

Your poo is set to save you dollars.

A proposal to buy a generator to run off biogas was put to the Invercargill City Council this week, two years after a report into its viability was first commissioned.

Council solid waste and drainage manager Malcolm Loan said the latest report shows the generator could save the council $43,000 a year in electricity costs at the Clifton Wastewater Plant.

The savings would cancel out the $204,325 cost of buying the generator. The Entec Generator would work by using the gas from the waste at the plant, to power a diesel 70kW motor, which would power about 30 per cent of the plant, Loan said.

In the 1980s a generator for a similar purpose was installed into the wastewater plant, but changes to electricity prices in the 1990s meant it became uneconomical, he said.

Now that generator is unusable.

The new generator, although small, would be economical for its size, using only some of the gas let off and changing it into electricity, he said.

The rest of it was already being used to keep the digestors - three big tanks full of sludge - warm, to ensure the breakdown of gases.

Infrastructure and services committee chairman Lindsay Thomas said the idea sounded positive.

However, it was sweetened by the fact that it would be partly funding by the Energy Efficiency and Conservation Authority, Thomas said.

The proposed generator would cost $204,325, plus GST, but 40 per cent of that would be funded by the authority.

The unit would then be used as a demonstration unit to show how successful small scale generators are.

Loan said the remaining cost could be funded by a 20-year loan from the council, but the project would be "cost effective".

After loan repayments and maintenance costs, he projected that it would make council a profit of $16,781 a year.

The issue was discussed at the infrastructure and services committee meeting and councillors voted in favour of the recommendation.

Loan said it could be implemented by October.

The Southland Times