Dubai's energy plan: Garbage power

Dubai: I As leaders from 192 countries grapple with the issue of climate change at the ongoing Copenhagen summit, Dubai has closed a tender this week for a ‘green' incinerator to generate electricity from trash.

Engr Abdullah Rafia, Assistant General Director for Health and Environmental Services at Dubai Municipality, in an exclusive interview with XPRESS, said: "We're replacing the current practice of land-filling, which is used by 95 per cent of the world's population. With this project, we're not opening any new landfills."

After years of planning, Dubai closed the tender on December 6 for international bidders to submit pre-qualification papers for the waste-to-energy (WTE) plant.

The plant is expected to be ready as early as 2013, helping to boost energy production in the emirate while ridding itself of the mounting municipal solid waste (MSW) and potentially earning for Dubai carbon credits, the future currency of global trade.

The plant is likely to cost Dh6.5 billion, most of it to come from the private sector through a finance-build-operate-own-transfer (FBOOT) scheme, said Engr Rafia.

The plant will be located at a 30-hectare plot in Al Aweer and is designed to burn 6,500 tonnes of waste per day.

Double gain

There are 600 plants around the world using WTE technology, producing electricity from turbines driven by steam generated by burning garbage. Dubai's version could be one of the biggest yet, and could produce over 150 megawatts - enough to power about 37,000 homes.

Dubai's move to use a trash incinerator will hit two birds with one stone: save on land and produce power without burning fossil fuel.

More importantly, Engr Rafia stressed, it will boost Dubai's carbon credits (CC). The Kyoto Protocol, ratified by 187 countries (including the UAE in 2005), allows governments and private firms to earn carbon credits which can be sold to companies emitting CO2 beyond their allowed limit.

But Kyoto commitments run out in 2012. This week (December 7-18) at Copenhagen, world leaders will negotiate and ratify a new international framework to replace Kyoto, calling for stricter emission controls.

"WTE is ideal for small countries with limited land," said Engr Rafia, referring to Dubai's land area of 3,885 square kilometres, nearly six times bigger than Singapore (682.7 sq km).

The small South-east Asian island nation alone has five WTE plants, one of which has been running for 30 years.

"From the safety and environmental standpoint, WTE is cleaner than nuclear energy," said a senior official who asked not to be named.

Waste for oil

Dubai produces 8,000 tonnes of MSW daily. At this rate, its three major landfills will overflow by 2015, said Engr Hussain Nasser Lootah, Director General of Dubai Municipality, during a September forum.

The US National Research Council of the National Academies estimates that one tonne of municipal waste combusted is equivalent to 45 gallons of oil.

If the WTE plant burns all of Dubai's 8,000 tonnes of waste daily, it can potentially save 8,571.5 barrels of oil per day, or about Dh809 million annually.

Critics say incinerators are a terrible idea for the 21st century, while supporters say it's better than landfills.

Stuart Flemming, CEO of Dubai-based EnviroServe which recycles electronics waste, said, "Incineration with energy recovery helps save land and avoids water contamination. There are plenty of examples of this technology."

He, however, called on authorities to implement stricter guidelines for residents to separate waste, maximise recycling and composting.

Tackling pollutants

Engr Rafia said using trash to generate power emits two-thirds less CO2 than coal when combusted.

As for hazardous air pollutants, Engr Rafia said: "We are looking to use the latest technology to mitigate any negative effects on the environment… it will be the strictest combination of EPA [US Environmental Protection Agency] and European emission standards."

Dubai seeks to use the latest sub-micron particulate scrubbers following the Environmental Protection Agency's Mact standard, which will screen out 187 hazardous air pollutants from incinerators.

Landfills are cheap, said Engr Rafia. But they pose a hazard due to possibility of water contamination while the decay of organic matter also releases large quantities of methane, a gas blamed for global warming.

DIOXIN fear

Dioxin, a by-product of burning wood, has been the target of anti-incinerator campaigners as it is believed to cause short-term liver damage without visible symptoms. Dioxin, also known to cause facial disfigurement, is a potent carcinogen and endocrine disrupter. Scientists say it is exceeded in toxicity only by radioactive waste

Know your trash

Dubai established waste management services in the 1950s

Dubai generates around 8,000 tonnes of waste daily

Seventy garbage trucks make about 800 trips daily to collect waste from different parts of the city

In some areas like Al Ras and Bur Dubai, trucks collect waste three times a day

Private companies transport 55 per cent of the waste they generate to the disposal and treatment sites

The general waste is taken to three landfills while hazardous and medical wastes are taken to the Hazardous Waste Treatment and Disposal Facility in Jebel Ali

FACTFILE:

One tonne of municipal solid waste (MSW) combusted equals 45 gallons of oil or 0.28 tonnes of coal

Thirty-five nations are currently using waste-to-energy (WTE) technology

More than 600 WTE plants are in operation

The global WTE industry processes approximately 170 million tonnes of waste per year

In the US, the WTE industry processes more than 26 million tonnes of waste per year

Globally, urban land-filling manages approximately 830 million tonnes of waste per year

(Source: US National Research Council of the National Academies)

How it works

1. Trucks dump the city's waste into a bunker

2. A crane hauls it into a furnace where it is burned

3. The heat is used to boil water, and steam is captured to drive power generators

4. Flue gases are pumped through different filters and ‘scrubbers' to remove pollutants

5. Ash collected; chimney stack emits clean air