The University of Southampton

Going green isn’t easy!

We hear a lot about green energy these days. Green energy is clean and environment friendly. It causes less pollution and is more sustainable.

But it's not very easy for the UK to go green completely. Keep scrolling down to find out why!

How much energy does each person use, on average, in a day?

National Grid has calculated that in the UK the total energy use per person per day is about : 110 kWh energy .

(this includes fuel, electricity, gas)

If we want to generate all our energy as clean green electricity then the UK will need to generate: 4.5 kW x 60 Million people = 270 GW electricity. This is almost FIVE TIMES the electricity that the UK can generate now.

(At the moment the UK can generate a maximum of 60 GW (60 gigawatts or 60,000,000,000 watts) electricity if using all its power stations and renewable resources simultaneously. See Generating Electricity section for the details)

National Grid has estimated the UK could generate enough electricity in renewable forms in the following ways:

National Grid has worked out that....

to generate 270 GW electricity that the UK would need to go green completely

we have to do ALL of the following: 

  • Build 60,000 wind turbines – most of them offshore
  • Half of all the roof area in the country covered with solar panels
  • Build 5 new nuclear power stations
  • 1000km of wave machines along the coast
  • Re-insulated almost all the nation’s homes, and turned the thermostats down
  • Flood the Severn Estuary
  • Give over about 25% of the UK’s food-producing land to energy crops


This isn't easy or cheap!

To install 60000 wind turbines - almost all off shore

we need to put up ONE PER HOUR to finish by 2025!


Could we buy and sell electricity between countries?

The UK has, for many years, bought electricity from France, which is transmitted via cable under the Channel.

Norway and Netherlands have invested in the NorNed Link: Length 580 km Operating Voltage ±450 kV. This has a capacity of only 700 MW (700 megawatts or 700,000,000 watts) and a cost ~£500 million. This is very expensive and provides tiny amounts of electricity compared with what the countries use.

And this amount is tiny compared with the 30,000 MW of mainly offshore wind generation planned for UK over the next decade at an estimated cost £30 billion (new nuclear plants are £7bn each for 4,400 MW)

The map shows an ambitious idea to link the whole of Europe so that each country can used its natural resources, and sell excess electricity when it can and buy when it needs to. But many countries are struggling to produce much 'green' electricity so there won't be much excess to sell to others.

Plus the power networks (eg the undersea cables, the DC switchgear, the DC/AC convertor stations) that can deliver electricity across such huge distances don't have a proven track record - will they work reliably?

Even if this works, there probably still won't be enough 'green' electricity to keep our homes and cars running.

See the 'research' section for more details.

Keeping Warm in the UK is Harder

Keeping warm?

At the moment the UK relies heavily on gas for its heating:

  • 84% of UK households have gas central heating - that's 23 million homes!
  • 63% of UK households cook on gas

On a very cold winter's night, the UK uses:

  • 300 GW power for heating
  • and 60 GW electricity.


If the UK wants to move to 'green electricity' for heating this means that:

  • 23 million households would need to remove their gas central heating and fit electrical heating eg heat pumps
  • The cost of removing a gas heating system and fitting a totally different system - new radiators, pipework etc is £14000 - £20000 per household. 
  • The UK would need to convert 1 house from gas to electric heating every 44 seconds until 2040 to finish the job!

So there's another problem:

  • For the UK, relying TOTALLY on electricity requires all our gas heating systems to be replaced
  • PLUS the UK would need much much more electricity generated - up to about FIVE TIMES as much!
  • And the UK National Grid would have to be made far more robust to carry the extra current - which means digging up lots of roads!
  • Replacing your gas central heating with an electric system eg. a heat pump, will cost every household over £14000
  • And to replace gas heating in 23 million homes with electric means converting 1 house every 44 seconds
  • Total cost £300bn!


Going all electric seems to be

                   impossible for the UK!