Sunday, May 9, 2010

GREEN TECHNOLOGY – cut carbon emission


Industry looks to green electric future

The world's electricity industry is setting out a plan for rolling out the

technologies needed to cut carbon dioxide emissions, showing how

ambitious plans to tackle global warming could be achieved.

Electricity generation accounts for about a third of the world's carbon

dioxide emissions from energy use, which in turn accounts for two-thirds

of all greenhouse gas emissions.

This is one of the sectors in which deep cuts in emissions are most

practicable – the technologies for producing electricity without emitting

carbon dioxide are either in use or close to deployment. Europe's

electricity industry has already committed to going carbon-free by 2050.

Electrification also offers the prospect of cutting emissions from other

sectors. Electric cars look a better bet than biofuels for greening road

transport. Electric heat pumps, which carry heat into the home, are an

alternative to burning coal and gas for warmth.

However, low-carbon power is going to be more expensive, at least

initially, and will require a huge investment in infrastructure as well as a

steep improvement in energy efficiency. In short, there will have to be an

entirely new type of electricity grid.

Advocates of carbon-free power talk about a "trinity" of generation:

nuclear, renewables – such as wind – and fossil fuel plants that capture

and store their carbon dioxide emissions.

Renewables and nuclear power are already well established. Renewables

are starting from a low base: in 2007 18 per cent of the world's electricity

came from renewable sources, of which 16 percentage points came from

hydro power, and just 1 each from wind and biomass. They are however

growing fast, with global wind power capacity rising by 29 per cent last

year thanks to construction programmes in the US and China.

Nuclear power provides about 15 per cent of the world's electricity.

Although a generation of ageing plants around the world is coming to the

end of their working lives, many countries, including China, India, the UK

and Italy, have ambitious construction plans.

Carbon capture and storage remains a nascent technology: no one has yet

proved that an integrated process can work on a commercial scale.

However, the US, Canada, Australia, the European Union and others have pledged billions of dollars to back demonstration projects. This suggests commercial deployment could be possible, given the right subsidies, around 2020. Even so, any transition to carbon-free generation will take decades.

Low-carbon technologies are generally more expensive than fossil-fuel plants: in

the case of some, such as offshore wind, they are a lot more expensive.

At the same time, power generation will not always be available. The

British government, which is backing Europe's fastest expansion of wind

power, is building into its plans for 2030 a huge margin of spare

generation capacity which can be used when there is no wind.

Managing demand will become crucial. Lars Josefsson, who is chief

executive of Sweden's Vattenfall, one of Europe's biggest electricity

companies, and president of Eurelectric, the industry association, says:

"The key to Europe's low-carbon future will be on the demand side." If

power supply is inflexible, it is particularly important that demand is

flexible to balance the grid.

A higher cost of energy will make consumers more worried about wasting

it. The electricity system will probably have to be based on a "smart grid",

which uses information technology to manage flows of power around the

network. This would include smart meters – which show consumers how

much energy they are using and also allow flexible pricing – devices in

homes that can send information and receive instructions, and even smart

appliances, that would switch off automatically when not needed. Higher

electricity costs at peak times will mean less spare capacity, which is

generally the most expensive and often the most polluting.

Keith Redfearn, general manager of transmission and distribution in

Europe for GE, one of the leaders in developing smart grid technology,

says: "The biggest opportunity is to flatten out the peaks in demand.

Electricity at peak times costs 15 times more than at off-peak times." Just

a 5 per cent reduction in peak demand in the UK would remove the need

to build five mid-sized gas-fired power plants, he says.

The smart grid would also make possible the widespread use of electric

cars, which could be charged overnight when other demand is low, and

more decentralised generation, allowing people to produce their own

power from solar panels, wind turbines or domestic boilers, and sell any


"It sounds like a pipe dream if you project forward to how the world could

look," says John O'Farrell of Silver Spring Networks, another smart grid

technology company.

"But think back to the early 1990s, and you would have never predicted

iPods and BlackBerrys, Twitter and Skype. All it needs is some smart

decisions to make it happen."

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