St Nicks

Centre for nature and green living

Making Waves: an introduction to renewable energy

The brand new development at Wakefield. Image courtesey of Barn Energy

This week our Recycling Coordinator Sam Taylor has swapped one resource for another in order to give us a quick and simple explanation of energy sources and renewables for British Science Week.

If you are interested in physics (or even if you’re not), you may know that energy cannot be made or destroyed but is simply transformed from one form to another. In most cases the energy we all use daily, whether it is to cook our food, heat and light our homes or wash our clothes comes from the combustion of a fuel (typically coal, oil or gas) into electricity. This isn’t a one stage process where combustion = electricity however, we did say this was a simple explanation so please have a look at this website for an in depth explanation.

Basically coal power is this on a large scale. Image courtesy of Pixabay

Basically coal power is this on a large scale. Image courtesy of Pixabay

Now, generally speaking when you set something on fire you can only do so once. Once it’s burnt, that’s it. It’s gone forever. This means that even if you don’t consider the effect that burning these fuels has on the environment, what is clear is that we have dramatically depleted our reserves of coal, oil and gas and can no longer rely on them as our main method of supplying energy. Once these resources run out, that is it. Done.

The gap left by these finite resources needs to be bridged, and what’s the easiest and most obvious way to do that? Find sustainable, renewable forms of energy.

Take for example one power source all around us – wind. Whilst it’s not very innovative, wind power is one of the most easily accessible forms of renewable energy. This is one of the oldest form energy sources too, as windmills were first used in Persia a whopping 3000 years ago!

Turbines in the backgound of a Windmill. Image courtesy of Wikipedia.

Turbines in the backgound of a Windmill. Image courtesy of Wikipedia.

These days they are known as turbines, and the only difference between a windmill and turbine is how the energy they harness is used. Turbines can be up to 120m tall and are usually grouped together in “farms”. Some people do take issue with them, considering them an eyesore or a potential threat to wildlife, however the evidence for the negative effects on wildlife are minimal as long as they are well positioned and maintained. And personally, I don’t see how they are any uglier than telegraph poles, smoke-belching power stations or electricity pylons.

Read on for an overview of how a few other renewables work:

This brings us to the final renewable energy source that we will cover of Marine, Wave and Hydroelectricity.

In honour of British Science Week  I’d like to explore this form of power in a bit more depth by looking at MeyGen, a new tidal stream project in Scotland launched September 2016. The system was developed by Atlantis Resources and phase 1 is set to feature 269 turbines generating enough electricity to power 175,000 homes.

One of the turbines installed by Nova. Image courtesy of Lockheed Martin.

One of the turbines installed by Nova. Image courtesy of Lockheed Martin.

The turbines stand around 15m tall and are installed directly on the sea bed, with 8m of clearance to the sea surface at the lowest tide. Working alongside the University of Aberdeen and the Sea Mammal Research Unit at St Andrews University, MeyGen monitor data to ensure that the turbines are running at capacity with minimal disruption to the environment. As water passes the blades they rotate, which turns a metal shaft in an electricity generator. The energy can then be transported and transformed into higher voltages and exported to the national grid.

This innovation follows hot on the heels of another British company Nova, who in August of 2016 managed to successfully send electricity on a commercial basis to the local grid. Nova built and installed an array of tidal power turbines at Bluemill Sound, Shetland. As you can see, Britain is leading the way in tidal energy (and quite right too – we are surrounded by tides).

The brand new development at Wakefield. Image courtesey of Barn Energy

The brand new development at Wakefield. Image courtesey of Barn Energy

A little bit closer to home is the brand new (opened March 13th 2017) hydroelectric power plant at Kirkthorpe, near Wakefield (West Yorkshire). It is the largest low-head river hydro plant to have ever been built in the county. It utilises the flow of the River Calder to rotate the turbine generating renewable electricity, the plant will be in use 24/7 for the next 100 years. The company responsible (Barn Energy) will be opening a second site on the River Aire near Knottingley before the end of 2017.

Here at St Nicks we think that renewable energy is vital to sustaining life. Current estimates state that we will run out of oil in around 50 years, natural gas within less than 55 years and coal in approximately 110, and these estimates don’t even factor in exponential population growth or the industrialisation of third world countries. If we include these, at a push we may only have up to 25 years of oil and natural gas left!

Trying to be sensible about our energy use by i.e. switching off lights, not leaving appliances left on standby, using energy efficient appliances and making sure your house is well insulated, will not only save energy but it will save you money. It’s time we started looking further into the future and thinking more about how our actions now and in the present can and will have severe impacts on our children and grandchildren.

It’s not all doom and gloom though, just look at the progress that has been made in the last 10 years!  For instance the strides in harnessing energy from marine sources like the tidal projects above have all occurred in the last decade. In 2008 less than 6% of our energy came from wind turbines. Now UK Government is aiming for 15% of total energy to come from renewables by 2020, and for 30% of energy to be generated by wind and solar by 2030. Considering that in 2008 less than 6% of total energy came from wind turbines, that’s a pretty big leap. According to reports (which are now 6 months old) the UK is set to meet its target for electricity generation by 2020, so let’s celebrate by embracing renewable energy to provide a bright future for the planet.

If you are interested in learning more contact us here at St Nicks or you can speak to the lovely people over at York Community Energy.



(This blog was edited on 20/03/17 to clarify some poorly written point… Sorry for any confusion)

15 March 2017 | Categories: Inspiration, Opinion Piece | Tags: anaerobic digestion, biomass, energy, renewable energy, solar, tidal, turbine, waves, wind