The Renewables Obligation is an instrument of financial support provided by the United Kingdom Government for generators of renewable electricity. The renewables obligation (RO) is set at a level which rises each year toward a UK and EU target. The RO is what is called a 'statutory instrument' used to incentivise electricity suppliers to produce electricity from renewable sources.

Wind turbines are admittedly limited in their usefulness by the fact that there may be no wind. Or, if there is wind it may not blow hard enough to generate maximum output at any particular time, or it may blow so hard that the turbines have to be shut down to prevent damage.

However, wind power even from relatively lower wind speed commercial sites is still a cheap resource compared to other renewable technologies, including wave power, tidal stream and even offshore wind farms that we must also be supporting. So we need to maximise production from as much commercial wind farms as possible on financial grounds, especially given the various other limitations on wind farms.

Generators get the same amount of ROC support for each MWh, no matter where in the UK they are sited. What could be fairer than that? Generators based in Scotland should therefore get the best price for their output.

ROCs can be traded separately from the electricity to which they relate. ROCs were drempt up to reward people who produce renewable energy by giving them extra cash. All suppliers (eg npower or British Gas) must get a percentage of the electricity they sell to you from renewable sources.

ROCs are better than green taxes in the eye of the public. Green taxes are defined broadly as any revenue-raising market-based environmental economic instrument , including for example, auctioned emissions allowances. So, the RO may be a form of a green tax which raises your electricity bill, but as this is not visible to the consumer it will remain popular with the public and government!

Wind farms are going to be the major benficiaries of the RO in the short to medium term. Greenpeace has coined the term ‘power stations at sea' which we think sums it up beautifully. It's the only technology that exists in sufficient capacity to make a dent on the challenging nature of the targets," say the experts.

In 2004 there were six offshore wind farms in operation in the UK which then saw another seven under construction and planning submitted for a further four. The pace has hotted up a lot recently and now many more are planned and being built.

The first offshore wind farm was the North Hoyle installation, built in 2003 and located in the Irish Sea off the coast of North Wales. Current large wind turbines are many times as tall as churches or trees, being over 100m to tip of blade. These wind turbines are on the scale of large industrial plant and can cover large areas.

Offshore wind can't get by without help from government, because the electricity is twice the price of onshore wind. The biggest ever wind farm which is planned to be built off Kent won't get built without government cash handout. Offshore wind is more viable off the coast of England where the waters are shallow than around many countries. In Scotland offshore wind would have to cope with deep water.