Turning everyday trash into clean energy

Advanced waste treatment systems could divert more than 95% of Sydney’s household waste from landfill and convert non-recyclable waste into a useful renewable gas to power city buildings and provide heating and cooling.

Rapid population growth in our cities means that by around 2021 our landfill sites will be full, with the nearest facility 250 km away. Around 400,000 truck movements a year are required to dispose of Sydney’s waste.

The City of Sydney’s draft advanced waste treatment plan shows how useful energy can be created from household waste, significantly reducing the loss of valuable resources to landfill and reducing greenhouse gas emissions.

The advanced waste treatment master plan aims to deliver an ‘energy from waste’ solution for Sydney by:

• recovering material and energy resources from non-recyclable waste so almost no waste goes to landfill;
• converting non-recyclable waste to renewable and non-fossil fuel gases; and
• converting these gases into substitute natural gases to inject into the gas grid to deliver low-carbon energy.

Advanced waste treatment by gasification is a long-term sustainable waste solution that is used in other major cities around the world. Gasification generates a synthesis gas, called syngas, from heating and decomposing the waste. The syngas can be converted into a substitute natural gas that has renewable energy content because of the organic material in waste. The renewable gas could then be used to power the city.

Any future plant would need to comply with the NSW Energy from Waste policy, which ensures there are no harmful emissions released.

Lord Mayor Clover Moore said landfill sites produce huge amounts of methane, a greenhouse gas with 25 times the global warming potential of carbon dioxide.

“It’s estimated this new technology could prevent around 196,000 tonnes of greenhouse gas emissions a year - equivalent to taking 43,556 cars off the road. The technology will also save ratepayers about $3.9 million a year by avoiding the waste levy costs of landfill. Every tonne of waste to landfill incurs a NSW waste levy of over $100,” the Lord Mayor said.

“Our residents have done a terrific job of recycling and we’ve already met our target to divert two-thirds of household waste from landfill.

“Currently, over 40,000 tonnes of household rubbish a year is processed to remove recyclables and produce low-grade compost, but one third of waste still goes to landfill. The advanced waste treatment plant could reduce this amount to virtually nothing.

“If we don’t try to reduce our waste, by 2030 the household waste of city residents is predicted to grow to 80,000 tonnes. This means after recycling and treatment, 27,000 tonnes of non-recyclable household waste would end up in landfill - equivalent to the weight of a cruise ship.

“An advanced waste treatment plant is a viable solution already used in other cities around the world.”

Along with the US and Canada, Australia is among the top three producers of waste per capita. Energy from waste technologies already plays a vital role in international waste management, with advanced waste technologies used across Europe, Asia and North America.

Operating under NSW’s current regulatory environment, advanced waste treatment can be effectively used to deliver renewable gas straight to the grid. This substitute natural gas can be used for electricity generation, heating, cooking and air conditioning.

This system is also designed to be able to fully integrate with future trigeneration plants to produce clean, local electricity, heating and cooling.

In Australia there are multiple facilities generating power from wastes such as sugar cane residue, recycling rejects and commercial food waste.

In the past 12 months, three major projects processing council-collected waste have been approved in Australia with more in planning.

For further information on the draft plan, visit www.sydneyyoursay.com.au.