Electricity is our most flexible form of energy and is used to power almost all industrial activities and domestic appliances. This electricity, however, must first be generated and distributed on wires around the country to these various end users.
Ireland’s electrical distribution system – the grid – is now creaking under the pressure of handling the rapidly growing supply of electrical power from renewable wind and solar energy sources.
Electricity is the movement of electrons in a conductor, usually a copper wire. We have known about one form of electricity, static electricity (accumulation of electrical charge on surfaces), since the Ancient Greeks (600 BC). Benjamin Franklin (1706-1790) proposed that electricity has positive and negative components and flows between them.
And in 1831, Michael Faraday (1791-1867), a largely self-taught genius, demonstrated electromagnetic induction by demonstrating that a changing magnetic field induces electrical current to flow in an adjacent copper wire. This led to the invention of the first electric dynamo, a crude electricity generator and the basis for the method whereby all electricity is now generated.
Alternating current (AC) varies in direction of flow and in magnitude, as opposed to direct current (DC) that flows only in one direction. Nikola Tesla (1856-1943) invented the AC motor and transformer – and AC is the standard for power transmission/use today.
Traditionally, we generated electricity by converting the chemical energy stored in coal, oil and natural gas (fossil fuels) into electricity in power stations and distributing this electricity around the country via the grid.
Burning fossil fuels releases warming carbon dioxide to the atmosphere. Electricity generated by wind turbines on wind farms and by capturing sunlight on photovoltaic receptors does not release carbon dioxide and increasingly supplement fossil fuel generated electricity nowadays. The aim is to become entirely independent of fossil fuels as soon as possible – “net zero” carbon emissions.
The basic architecture of national grids was established when sources of primary power were restricted to fossil fuels. Grids have been extended/improved since that time, but now struggle to cope with recent greatly-increased inputs of electricity from solar and wind power.
We take reliability of electrical supply for granted and, so, the recent Iberian Peninsula electrical system shutdown last April, leaving the entire Spanish and Portuguese mainland without power for several hours, was a salutary reminder of our reliance on the grid.
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The Spanish government has issued a report stating this shutdown was triggered by operator mismanagement and not by difficulties in accommodating electricity generated by solar and wind power.
Problems with the UK grid were recently outlined by Justin Rowlatt on BBC News. He cited a typical example of the problem – on June 1st and 3rd this year, near gale-force winds blew into Scotland’s Moray Firth wind farms 21km off the northeast coast.
Operating at maximum capacity, these wind farms should generate enough electricity to meet the needs of well more than one million homes, but the grid is sometimes unable to accommodate their output. Ocean Winds, the company that built and operates the Moray Firth wind farms, was paid £72,000 (€83,000) not to generate power during a 30-minute period on June 3rd. Power output was restricted several times that day.
Such payments are made most days in the UK and also arise in Ireland. Seagreen, Scotland’s largest wind farm, was paid £65 million (€75 million) last year to restrict output 71 per cent of the time and, so far this year, such balancing of the grid has cost the UK more than £500 million (€574 million).
The UK National Electricity System Operator warns the total cost could approach £8 billion (€9.1 billion) a year by 2030. This pushes up everybody’s energy bills and contradicts government promises that achieving net zero would also deliver cheaper electricity.
The UK operates a single national electricity market. Its government was considering breaking this into smaller regional markets, hoping to make the system more efficient and deliver cheaper bills. This seemed sensible but in July it announced it was dropping the plan.
The UK and Ireland need to build more transmission capacity quickly and new grid architecture must be planned well in advance to attract investors to build these assets in a timely fashion. At present, very cumbersome planning systems greatly delay grid developments in both countries. Current planning protocols must be urgently reformed.
William Reville is an emeritus professor of biochemistry at UCC
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