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Drax refit for power station beyond UK gas turbine needs

There was something worrying in the back of our minds as we poured over the decision due shortly on the UK Drax power station, and its request being pondered by the UK government to allow it to convert its remaining coal fired power stations to gas.

The worrying thing in the back of our minds was the statement out a month ago from the UK Energy and Clean Growth Minister, Claire Perry about budgeting $733 million to subsidize wind contracts and to train staff in renewables.

This came at a time when 2 nuclear power station developments were shelved in the UK, because they were seen to be too expensive when compared to wind projects, and yet here was the government subsidizing wind, which definitely needed it ten years ago, but really can probably hold its own right now. But the accompanying message was this simple statement that the UK was pursuing an energy strategy of 30% of electricity from offshore wind (which is mostly experimental and more expensive than onshore), 30% from nuclear (which no-one wants to build) and 30% from gas power stations fitted with technology to capture carbon emissions and bury them, which no-one has ever done. There was not a single mention of solar energy, currently reducing in cost the fastest, nor grid scale batteries or virtual power plants.

One of the alarm bells that went off at the time was that mention of carbon capture, as we know few companies that have tried it and none that have done a really good job of it.

What is wrong with a world where we simply carry on digging up fossil fuels, as long as everywhere we burn them, we collect the carbon out of the exhaust – on our cars, our home gas boilers and in power plants? Well what is wrong is the continuing disruption on to the environment of digging up precious resources and the tendency these have towards accidents like the Deepwater Horizon BP Oil spill. Also the idea that some people will claim to be capturing the carbon, but cut corners and simple lie about releasing it into the air.

Disturbingly the Drax power station has already converted about two thirds of its capacity to wood pellets, describing it as carbon neutral, and burning mostly US wood, because the amounts involved are staggering and you could not grow that in the UK. It is described as carbon neutral because the wood is supposed to be growing at the same rate – well you’d need a forest the size of the UK to manage that, but also because Drax is “experimenting with carbon capture.” The part of the power station that has been converted to wood outputs less carbon now than when it used coal, but perhaps as little as 10% less. It continues to be one of the most polluting power stations in all of Europe. And as for whether or not the wood that it uses is replaced, that is shrouded in some mystery with claims and counter claims from the renewables lobby.

So this week when the Drax proposal was sent off for the UK government to consider, it has the feel of a stitch up about it.

The government wants someone to build a big gas power plant, and try out carbon capture, so who better than a company that was once part of the government owned power generation, which already has some experience with carbon capture technology?

Currently the form of carbon capture Drax uses is spraying chemicals into the smoke it produces. This binds with the CO2, and that process is then reversed to create carbon rocks that can be used for something else. But Drax has only scratched the surface of carbon capture, and it is likely that UK government will give it a lifeline, and money to finish off perfecting the carbon capture and apply it to gas.

So far it has released no information on how much of the carbon in its wood pellet process is captured and at what cost in terms of both cash, and chemicals and electricity. Drax power station at present creates 6% of the UK’s electricity, around 3.6 GW of what it calls reliable and flexible power generation.

The entire Drax Repower project is about converting the remaining one third capacity that is coal to gas plus adding 200MW of battery storage. The press release presents this as a way to help enable a zero carbon, lower cost energy future. It pitches the idea that the IPCC wants to get to 2050 with 85% of generation on renewables and a remaining 15% on technologies like gas, biomass, hydro and pumped storage.

We know these last 3 are virtually stagnant globally, apart from coal conversion projects, because they are no longer economically viable. Dams and hydro are great, but cost too much to build from scratch and take too long.

Quite rightly environmental pressure groups are up in arms about this proposal. They figure that the biggest polluter in the UK will take a drop of 10% to 15% in its CO2 emissions and pretty much carry on as before, while uttering pro zero-carbon mantras.

Gas does present less of a CO2 issue than coal and the IPCC certainly accepts that some gas plants need to be maintained, as much for grid stability as anything else. But in most cases it makes sense to partner gas turbines with wind and solar and battery, in a Virtual Power Plant, in small chunks all over the country. Instead Drax seems to want all of this gas generation in one place, with an unquantifiable amount of carbon capture thrown in.

This is not the only way of converting coal plants. In Germany for instance

There is a project to convert existing coal power plants to energy storage, by attaching a huge battery store to the steam fired boiler that is already in place at coal plants. That idea relies on using molten salt in thermal storage tanks, heated using excess renewable energy. And instead of having a “chemicals” wasteland around the coal chimneys, the plan in Germany is to put as much local solar on the site as possible, covering up 50 years of abuse to the countryside.

The cabling infrastructure is then already in place and a molten salt store battery can hold it and release it through heating the water for the gas turbine. It can also partner with nearby wind and solar plants, and provide their storage and connection to the grid. It’s a sensible plan. It is far more elegant than the Drax proposal, which has drawn thousands of complaining signatures from all over the country on a petition calling for the government to stop.

Putting our cynical hat on for a moment, there is every chance that the Drax deal is ushered through leaving a rejuvenated UK facility which is very large, and which can run for a further 25 years, polluting (almost) every bit as badly as it has in the past. The only good thing is that because of its sunk cost in infrastructure, it will probably make good profits.

The biggest worry is whether or not a facility of this size would use natural gas, or would it require imports or fracking to feed it over time, and all of the additional potential issues with methane release that fracking brings.

The decision on Drax will be made in October, and who knows who will be running the country by then, given the mess that Brexit is in.

The UK government has already given planning approval for about 15GW of new large-scale gas plants, and it has been estimated that the UK needs just 6GW of new gas turbines in the run up to 2035. So it has already tied itself to a future where it misses IPCC targets.

The Drax CEO in a statement has dropped the tasty morsel of being able to get rid of coal production far earlier than planned in 2025 – protecting jobs. But at what cost?

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