Renewable energy is always in the news – but it’s a complex subject which is often misunderstood.

That’s why we asked the experts at ESC (Energy & Sustainability Centre IOM) to give us some simple, easy-to-understand guides. Here’s the first in this series.

What is renewable energy?

Renewable energy is generated from a natural source which can be replenished faster than it is consumed.

For example, wind is an inexhaustible source of energy (as we know only too well here in the island!) – so this is classed as renewable.

Also, most renewable sources of energy are classified as ‘sustainable’ in that they do not directly produce greenhouse gases like carbon dioxide (CO2). On the other hand, fossil fuels (natural gas, oil or coal) are not renewable energy sources because they take millions of years to form whilst using them produces CO2 which affects the climate. 

Is renewable energy the same as ‘green’ energy?

In most cases, renewable energy can also be viewed as being ‘green energy’ (green meaning that it does not significantly harm the environment or affect global temperatures). Nonetheless, there are lesser impacts with renewable energy, for example the visual effect of wind turbines and the carbon dioxide from using natural fuels such as wood.

What is meant by ‘power capacity’

The power capacity of a renewable energy project is the maximum amount of power that it can produce in ideal conditions.

The power capacity is usually reported in megawatts (MW) which is the same as a million watts or 1,000 kilowatts (kW).

The natural conditions which produce renewable energy such as wind and sunlight vary significantly over the day, weeks and seasons.

This means that maximum power is rarely achieved. The average power from a 30 MW capacity wind farm in the Isle of Man is expected to be around 9 MW and from a solar park around 3 MW.

On average, the Isle of Man currently consumes around 41 MW of electricity (mostly generated from gas fuelled power stations), 90 MW in heating (in gas and oil) and 58 MW in transport (in petrol and diesel).

 Look out for more 'Ask An ESC-pert' articles on renewable energy coming soon