How does the electricity grid work?
It can be hard to get your head around how electricity gets from where it’s generated ready to be used in your home.
In this article, we simplify how the electricity grid works, explain how supply and demand is managed and describe what happens when you switch to a renewable energy tariff.
So how does the grid work?
The electricity grid is made up of two different types of networks – the national transmission network and local distribution networks.
A useful analogy to help understand the differences between the two networks is a comparison with our motorway and local road networks.
The national transmission network operates at a very high voltage and works like a motorway to channel power at high speeds around the country. Large scale generators, such as nuclear power plants, offshore wind farms, gas power stations, as well as international interconnectors, all feed power into this network.
The distribution network is still high voltage, but lower than the transmission network. This network works more like B roads, distributing electricity locally to homes and businesses. Smaller scale generators feed into this lower-voltage network, such as small onshore wind farms, solar farms, hydro generators and biogas.
Electricity then passes through substations to reduce the voltage further and make it suitable for using in our homes.
How is energy supply and demand managed?
National Grid ESO is the electricity system operator for Britain. Their job is to make sure that energy supply matches energy demand for every second of the day. They closely monitor how demand is impacted by weather, time of day or unexpected surges in usage (such as half time in a major football match) , and they balance that with what is being added onto the grid.
Good Energy’s Power Pause helps you to be part of the solution to balancing the grid by rewarding you to use less energy at peak times.
What happens when you switch to a renewable energy provider?
When you switch to a renewable energy provider, we don’t connect a separate ‘renewables only’ supply to your home – so what does happen?
All energy suppliers have to source enough electricity to match their customers usage. Good Energy makes sure that 100% renewable electricity, from solar, wind, hydro and bio-generation, is supplied to the grid to match our customers’ demand. We do this by having contracts in place with a community of over 2000 independent renewable generators across Britain.
We also strive to match our customers usage with renewable energy in real time, down to every half an hour of every day. A lot like what the National Grid ESO does on a national scale for the whole country with all sources of electricity, Good Energy does for its customers with renewable only sources.
This is something we are now rather good at. For the past five years, we have matched our customer’s demand volumes with the power we buy from our community of local generators – over 90% of the time, in half-hour intervals across the year. We are very proud of this and are aiming to improve this percentage every year.
What’s good about having lots of local generators?
Having thousands of smaller scale generators spread throughout the country is strategically very important – for two main reasons.
- A lot of energy is wasted by channelling high voltage power around the country and passing it through multiple substations. It’s more efficient to generate it and use it locally, in your own town or even in your own home.
- Having thousands of small generators is vital for energy security. This is because lots of small power stations are less likely to fail than a handful of large ones.
This is our model at Good Energy. We’re proud to be supporting local economies and encouraging the growth of the small-scale renewable energy industry.
Read our report on how Britain could transition to a low carbon energy system in one generation.
Want to find out more?
Read our articles for more information about how the electricity grid works.
