From a Coal Past to a Low Carbon Future for the U.K.’s Largest Power Plant

Striving for Coal-Free

The U.K. government has undertaken to be coal-free for electricity power generation by 2025, which is some pledge for a country sitting on coal reserves said to be sufficient for 300 years of demand (albeit much of it is at depth and not as economically attractive as it may sound).
In 2012, the U.K. produced 40% of its power from coal, much the same as in the U.S. at the time. Unlike the U.S., where coal now makes up a declining but still substantial 30% or so, in the second quarter of this year coal usage in the U.K. fell to 2.1%.
In fact, on April 21 – a particularly windy day – the U.K. was coal-free for 24 hours for the first time since the onset of the Industrial Revolution.
The major beneficiaries will come as no surprise for anyone familiar with British weather.

The Renewable Energy Wave

The share of electricity coming from wind and other renewables, including biomass, was nearly 30% in Q2 this year, with the vast majority of that coming from wind turbines, The Telegraph reported. Taken as an average over the year, 2016 was the first year Britain got more energy from wind, (11.5%) than coal (9.2%).
The Telegraph article explores the rapid decarburization of the U.K.’s power generation landscape by reviewing the changes at Drax in North Yorkshire.
What was western Europe’s largest coal-fired power generation site — consuming 9 billion tons of coal per annum in six massive boilers to generate up to 3.2 GW of electricity just a few years ago — has transitioned to near 70% power generation from biomass, importing 20,000 tons a day of mostly U.S. biomass pellets to feed three of its converted boilers.
After Drax invested millions to make the transition, the U.K. government did a U-turn on biomass subsidies, withdrawing much of the support. Undeterred, Drax is planning to convert its remaining coal-fired boilers to natural gas and at the same time build the country’s — some suggest the world’s — largest battery storage facility.

A Variable Approach

Wind power in the U.K. continues to enjoy some subsidies despite recent policy changes.
But even so, power costs from new offshore wind farms are coming in well below the level agreed for proposed and planned nuclear facilities, and even rival older natural gas plants.
The problem, as we so often hear, is wind and solar are too variable for current national grids to comfortably manage more than a proportion of power coming from such sources. It is widely accepted that national grids need a shock absorber to provide a buffer between fluctuating demand and variable supply. In the old days of “always on” electricity supply from coal, nuclear and gas, this was relatively simple. But with on/off supply sources like wind in the mix, the national grid finds balancing supply much more challenging.
Drax sees a future in providing a mix of very low-carbon electricity supply through renewable wood pellet biomass power generation and natural gas. They aim to combine that with great flexibility in meeting the grid’s need for buffer supply by battery storage and flexible gas turbines that can be ramped up and down within minutes to meet demand or divert to storage in times of plenty.
Drax is not alone in seeing this flexibility as being worth a premium price — but Drax is ahead of the curve in seeking approval and commitments to build it.
However, as much as the environmental lobby may urge policymakers to support zero-emission power generation, the reality is grids need suppliers like Drax to make wind and solar viable at high levels of total supply coming from variable renewables.
Free Download: The September 2017 MMI Report
Britain is becoming increasingly reliant on wind power. Generators like Drax create the means to achieve that while keeping the lights on.