Renewable Energy FAQs

Traditionally, we have relied on fossil fuels such as coal and gas to provide our energy. Fossil fuels are a finite resource and, as such, could run out one day. That’s why we are looking to alternative sources to provide our power and heat needs. Furthermore, the European Government has passed legislation which requires us to meet specific renewable energy targets. As a country, the UK has signed up to generating 20% of our energy from renewable sources by 2020.

Renewable energy comes from a source that is not depleted when used, such as wind, hydro or solar power.

One of the differing aspects to renewable generation is that is can be achieved on a micro level (solar PV panels on houses) and macro scale (tidal lagoons in the sea). We can generate energy using solar, hydro, wind, marine and geothermal sources or any combination of these.

The media talks about renewables being intermittent and, because they are intermittent they are unreliable. It’s true that our wind farms don’t generate electricity when the wind isn’t blowing; and that solar panels don’t generate electricity at night time. But we prefer to think about the generation being variable and the variation being predictable. When the wind isn’t blowing the sun may be shining or the tide coming in. The Thrive Renewables portfolio is spread around the country and we know from experience that there are big geographical differences in natural resource too. We have a national electricity grid to support the movement of electricity between points of supply and demand.

There have been huge steps forward in forecasting over the last decade and we can now predict things like wind speed and cloud cover very accurately at least 24 hours ahead. This gives the National Grid the opportunity to ensure renewable generation is contributing to our country’s base load demand and enough lead time to reduce output from the fossil fuelled or nuclear plants we’ve relied on for this in the past. With the continued advance of technology and evolution of smart grids and storage solutions the variability of renewables can be managed. But there has to be an underlying desire from political and commercial quarters to drive this forward.

Wind farms generate electricity around 80-85% of the time. The power is free
 and is converted to electricity very efficiently with none of the thermal waste inherent in fossil fuel plants. It is sometimes alleged that wind turbines are 30% efficient. This figure is based on the ‘load factor’ which is based on the theoretical maximum output and is not the same as efficiency. Conventional power stations in the UK run with an average load factor of 50-55%*.

* Common concerns about wind power – Centre for Sustainable Energy, May 2011

The average wind farm is expected to generate at least 20-25 times the energy required in its manufacture and installation over its lifetime, and the average energy payback time for a wind farm is 3-6 months*.

*Common concerns about wind power – Centre for Sustainable Energy, May 2011

Wind turbines do inevitably create noise. The evolution of wind farm technology has, however, rendered mechanical noise from turbines almost undetectable, with the main sound being caused by the blades passing the tower. In the UK there are strict guidelines as part of the UK planning regulations to prevent undue noise pollution, and this, combined with the quieter design of modern turbines, means the noise is comparable to outdoor background noise.