Bye bye coal

So last night the last of the UK’s coal-fired power stations was turned off for good. Ratcliffe-on-Soar is no longer generating electricity by burning coal.

Coal has been reducing in significance in the UK’s energy mix for some time, as data from the National Grid show, below.

So what if we expanded this policy to cover the whole world?

The baseline scenario

The UK may be the first G7 country to remove coal from our energy mix, but what if every other country adopted the same policy?

Thanks to Climate Interactive and their En-ROADS Climate Solutions Simulator, we can see what the effects might be.

First, let’s look at the baseline scenario. This is what the state of the world might be if societal and technological changes were to continue at their current rate of progress with no policy changes.

Here is the energy mix going out to 2100.

And here is how greenhouse gas emissions change in that baseline scenario – assuming no policy changes are made.

In this scenario, we get a global temperature change of +3.3C by 2100. Scary.

Let’s make some changes

Using the En-ROADS Simulator you can make a lot of changes. You can move sliders, you can fine-tune settings, and you can even change the underlying assumptions. It’s hugely flexible and you can simulate all sorts of possible policy interventions to see what impact they might have.

Let’s change settings to do with coal to simulate the whole world following the UK and stopping generating electricity using coal.

Here’s what the energy mix would look like.

What happens to that all-important measure of greenhouse gas net emissions? As we reduce coal use towards zero, greenhouse gas net emissions fall – because we are no longer burning as much coal.

Once coal disappears from the mix, the curve starts rising slowly again as energy demand continues to rise.

Importantly, the total CO2 in the atmosphere is reduced in this scenario. That’s a Good Thing.

Here’s what we changed in the model.

We’ve reduced new coal infrastructure completely, i.e no new infrastructure will be built to generate electricity from coal from now on. This policy is phased in over 10 years.

We’ve also reduced utilisation of coal processing plants and coal-fired power plants, completely ending coal utilisation as a fuel – also phased in over 10 years.

We also increase the annual retirement rate of coal plants used for electricity to 10%/year.

As a result you can see the coal primary energy demand (graph on the right) plummet to zero by 2034. Look at how the energy demand from coal drops to zero by 2034, compared with the baseline scenario.

Co-benefits

It’s not just about greenhouse gas emissions, although those are hugely important. When you make changes that reduce emissions, you get other benefits as a result.

What sort of results do we get?

Firstly, a reduction in the global temperature rise. The baseline model has a rise of 3.3C. Now we’ve reduced that to 2.9C. Not as far as we need to go, but it’s a start.

This comes about because of a change in the trajectory of the greenhouse gas concentration curve.

We also get other important co-benefits, things that have a positive impact on human health, the ecosystem, sea level rise, etc.

Here we can see how the removal of coal from the energy mix dramatically reduces air pollution from energy generation.

This graph shows a dramatic reduction in PM2.5 emissions, very small particles (2.5 micrometers or less in diameter) that can be easily inhaled and cause health problems.

This is great, right? Well, it’s a good step in the right direction, but it’s not The Solution.

Here’s the global sources of primary energy graph again. Notice what happens to the natural gas wedge (blue).

When coal use is reduced, demand for energy is still significant, so gas gets used to compensate. Unless there are also restrictions on gas, its demand will go up in response to expensive (or no) coal.

How do we solve that? One solution is to tax (or restrict) the use of oil and gas as well. But that makes energy more expensive for everyone, and life more difficult for those who struggle to afford energy.

It’s a difficult problem. And as you can see here, although changing policy on the use of coal is a high-leverage solution, on its own it is far from the entire solution.

Getting closer to 2C

We need to keep coal, oil and gas in the ground for any solution to bring us close to 2C.

As the folks at Climate Interactive say “it takes many seed to plant a garden”. There is no one solution that is going to fix the climate. But removing coal from our energy production is a step in the right direction.

Here’s the scenario we built.

Want to explore further? Have a go at making your own scenario to bring the temperature rise to 2C or better? Go have a play with the simulator, and share your scenarios!