Electrochemistry: a new way to use excess wind power?

Pioneering research at Copenhagen University is exploring a new way of using Denmark’s excess wind power. CAT Information Officer Mim Davies talked to one of the researchers to find out more.

Wind power in Denmark has a very different story to wind power in the UK.

Despite the UK being the windiest country in Europe, wind power only made up 11% of our electricity supply in 2015. In the same year, Danish wind farms produced the equivalent of 42% of the country’s electricity demand.

At times, Denmark has more wind power than it needs, and ends up exporting it to neighbouring countries.

I talked to Bethan Davies, a chemistry PhD student at Copenhagen University, Denmark, about how her research team are looking at a new way of using this excess wind power.

You’re a chemist. What does chemistry have to do with wind power?

A huge variety of products, from building materials to medicines, are made from a range of synthetic chemicals.

A lot of the synthetic chemicals used in manufacturing are produced in chemical plants on a large scale. The conventional production of chemicals involves high temperatures and pressures to drive chemical reactions. These are usually achieved by burning fossil fuels, such as natural gas.

At Copenhagen University, we’re investigating chemical reactions that are driven by electricity, rather than high temperatures and pressures.

When an electrical current is passed through a solution, chemical reactions can happen. Different reactions produce different chemicals. We’re looking at optimising this process, so we can produce a number of chemicals that would otherwise be made by conventional methods.

The electricity for these processes could be supplied by fossil fuels but also by renewable sources, such as wind power.

Common uses for synthetic chemicals

Synthetically produced chemical Uses
Organic carbonates For producing the electrolytes used in batteries
Acetylsalicylic acid Used to make aspirin
Para-aramid polymers In optical fibre cables
Meta-aramid polymers Used to make the hood on a firefighter’s mask

Could excess wind power be used for electrochemical production?

Yes, because chemical demand is not always continuous and many chemicals can be made in batches.

Turning conventional chemical production on and off can be energy and time intensive, as high temperatures and pressures have to be reached to get the reactions started.

Electrochemical reactions don’t need high temperatures and pressures, so electrochemical plants could be turned on and off more easily. This means they can make use of bursts of excess wind power. Using excess wind power to produce chemicals would mean using less gas and other fossil fuels in Denmark.

What kinds of challenges are you facing?

We need to make electrochemical processes economically competitive compared to conventional methods; otherwise there will be a large resistance to change.

The tools available to us as researchers at Copenhagen University allow multiple levels of understanding. We can perform theoretical analysis by computer simulations, perform experiments that look at what is occurring at the atomic level, and we can quantify yield and efficiency.

We are investigating several electrochemical reactions, but to make a complete electrification of the chemical industry many more important chemical reactions will need to be studied and the processes developed.

To find out more about this project you can follow Bethan’s research team on Twitter @NanoElectrocat

Excess wind power and Zero Carbon Britain

In a 100% renewable energy powered UK, wind power would play a large role.

CAT’s Zero Carbon Britain: Rethinking the Future report looked at using surplus energy (e.g. at windy times) to electrolyse water to hydrogen, and then upgrading the hydrogen to synthetic methane. Methane is easier to store than hydrogen and can be burnt in power stations to produce electricity when the wind isn’t blowing. This offers a way to store energy that works with existing infrastructure.

Zero Carbon Britain also suggests some short term energy storage options we could use when we have too much wind power. These include pumped storage, smart electric car charging and heat storage.

To find out more about our Zero Carbon Britain report, visit www.zerocarbonbritain.org or get in touch with our Information Service – info@cat.org.uk

Mim Davies is one of CAT’s Information Officers. She is a physics graduate with an MSc in Water and Environmental Management. She first came to CAT to volunteer in the engineering department during the cold winter of 2010.