Kathryn Porter on the Problems Inherent in Renewable Energy
Kathryn Porter, one of the UK’s leading energy experts, presents a damning critique of the UK's renewable energy policy, particularly focusing on intermittent sources.
Overview
Kathryn highlights the follow key issues in this video from a recent talk in Wells:
Fundamental Incompatibility with the Grid Design. Basic physics and engineering means that renewables are incompatible with existing grid infrastructure.
Grid Instability and Blackout Risk Due to Lack of Inertia. One of the most significant fundamental limitations of renewables means the grid will become increasingly unstable.
High Costs Passed to Consumers. Total annual costs for subsidies, environmental levies, and carbon taxes are £17 billion per annum and increasing, with almost all of this added to electricity bills.
Inefficient Use of Capital and Resources. The existing grid infrastructure is old and requires extensive upgrades to handle renewable energy generators which require relatively more wiring than conventional power stations.
Negative Economic Impact and De-industrialisation. Since 2006, £220 billion has been spent on decarbonisation efforts that have provided no economic benefits
Regulatory and Infrastructure Challenges. Long lead times and excessive regulation mean that 2030 targets are wholly unrealistic.
In the remainder of this post I will talk about these in more detail based on Kathryn’s talk.
Fundamental Incompatibility with the Grid Design
Firstly, some basic physics.
The UK's electricity grid was designed for alternating current (AC) generated by large, conventional power stations like gas, nuclear, and hydroelectric turbines. These generators produce a consistent sine wave of current and voltage at a stable frequency (50 cycles per second). This frequency is crucial for the operation of connected electrical equipment.
Conventional generators are large, heavy machines with significant inertia, which means they resist changes to their speed and motion. This inertia helps stabilise the grid frequency.
In contrast, wind and solar generators produce direct current (DC) and use electronics to convert it to AC for the grid. These electronics are passive; they look at the grid's wave and only inject electricity if it's behaving as expected. If the frequency goes outside their operational tolerance, they turn themselves off to protect from damage.
Grid Instability and Blackout Risk Due to Lack of Inertia
As more renewables are added and conventional generation is reduced, the grid has fewer units creating the stable AC wave and less ability to resist changes to frequency. The electronic converters in wind and solar units don't provide the same inertia as conventional turbines. A low inertia grid becomes really unstable.
If a fault occurs (like equipment breaking, lightning strikes, or fires), frequency can vary. In a low inertia grid, instead of conventional generators' inertia acting as a brake on this change, the passive renewable units simply turn off. This was illustrated by the recent Iberian power grid collapse; a fault caused frequency variation, leading to renewables turning off, and quickly the entire grid collapsed into a full blackout within minutes.
The UK is increasingly running a low inertia grid and has experienced unexplained voltage oscillations, leading to disconnections. Running a low inertia grid increases blackout risks even if there is enough generation if it's not the right type.
High Costs Passed to Consumers
Contrary to the perception that renewables are "free" because the wind and sun are free, the machines that convert them into electricity are expensive. These projects require subsidies, which are ultimately paid through consumers' bills. The most recent subsidy price for offshore wind in the UK was £83 per megawatt hour (MWh) in today's money, which is £10/MWh more expensive than the average wholesale gas price that is widely complained about.
Despite this high subsidy, major developers are cancelling projects because they state the economics do not work. Furthermore, because renewables are intermittent, an entire separate set of generation (primarily gas power stations) must be built and paid for to be available when it is not windy or sunny. This backup is particularly crucial during peak demand in winter dinner time, when there is zero solar energy. These availability payments for backup generation also come through bills. Total annual costs for subsidies, environmental levies, and carbon taxes are £17 billion per annum and increasing, with almost all of this added to electricity bills.
She asserts that the claim that renewables are cheap and will lower energy bills is untrue and a "very dangerous fiction" for intermittent sources. She described the Levelized Cost of Energy (LCOE) metric, often used to argue renewables are cheap, as an "artificial measure" that doesn't include the full system costs needed for reliable supply, focusing instead only on short-run operating costs.
Inefficient Use of Capital and Resources
Renewables, particularly wind farms, have low energy density, meaning they require a much larger geographic footprint and significantly more wires and connections than conventional generation. An 800 MW wind farm might require 180 times the wires of an equivalent gas power station, adding considerable connection costs.
Focusing investment on connecting these dispersed renewable sites has led to neglect of legacy grid infrastructure, which is often old (some transformers from the 1960s) and struggling to cope with operating in a way it was never designed for.
Building large numbers of renewable units also requires extensive mining for materials, which Kathryn described as "insane" for something that only works a third of the time, representing a really inefficient use of natural resources.
Negative Economic Impact and De-industrialisation
High energy costs resulting from the UK's energy policy are forcing manufacturing to move overseas to countries with cheaper, often dirtier energy sources, leading to de-industrialisation in the UK. This offshoring does not reduce global emissions; it increases them because the manufacturing uses dirtier energy abroad, and the finished goods then have to be shipped back, which is inefficient and adds further emissions.
Overall, the UK's energy costs have been made fundamentally uncompetitive, significantly worsening the situation for businesses alongside other factors like taxes and employment costs. Kathryn calculates that since 2006, £220 billion (in today's money) has been spent on decarbonisation efforts that have provided no economic benefits; the UK would have been £220 billion better off sticking with gas.
Regulatory and Infrastructure Challenges
Keeping the lights on is becoming very difficult as the existing gas generating fleet ages (some units from the 1990s) and retires. Replacements face five-year lead times for new turbines. Achieving targets for grid expansion requires building infrastructure rapidly, but there are long lead times for critical equipment like transformers (two to four years).
Furthermore, regulatory bodies and quangos are slowing down necessary infrastructure projects and adding significant costs. For instance, environmental statements for nuclear projects like Sizewell C run to 40,000 pages partly as a defensive measure against judicial review, adding cost regardless of whether a review happens.
She also criticises regulators for focusing narrowly on site-by-site impacts rather than considering the national interest and the overall system impact of energy density differences.
Summary
Kathryn demonstrates that renewables, particularly intermittent ones, are fundamentally incompatible with the existing grid design and lead to significant costs, instability, and economic harm.
She suggests that nuclear power, which produces AC, runs continuously, has high energy density, and works reliably with the existing grid, is a more suitable option for decarbonisation. She acknowledges that current regulations make it more expensive than necessary.
Building new gas power stations is also necessary to maintain security of supply in the short to medium term.