Author: admin

The toolmaster

22 January 2017

Power generation
Andrew Storr

Before Drax Power Station was a part of Andrew Storr’s career, it was a part of his local environment.

“When I was at school in Selby they were building the second half of the station,” he says. “We could see them building the cooling towers out of the classroom windows.”

But it wasn’t until a careers advisor brought an old cine film of the power station into class that he considered working there. “Part of the film was them stripping the turbine and I watched it and thought, ‘I want to do that,’” he says.

Today, Storr does more than strip the turbines, he’s part of the engineering team that oversees them – a job that needs to be taken seriously.

“If the turbine’s off, forget the rest of it: we’re not generating electricity ,” he says. “We’ve got to make sure the turbine and the generator are absolutely as bulletproof as possible because we’ve only got one per unit.”

Considering the conditions each one comes under, this is no easy task. “The turbine shaft weighs 300 tonnes and spins at 3,000 rpm. The high pressure turbine is 165 bar, and temperature-wise, the steam running through it making it spin is 565 degrees centigrade.”

Bulletproof is an understatement. When it comes to carrying out maintenance on a turbine, it’s more than likely you’ll have to visit Storr’s workshop.

Andy_Storr

Fixing the governor

The workshop hasn’t always been there. It all started fifteen years ago when a piece of equipment broke. It was a turbine governor relay, a  precision hydraulic actuator that keeps the turbine spinning at the right speed. Drax needed a new one.

“They’ve got to be 100% reliable,” Storr explains. “If they lose control of the turbine, it can either come to a grinding halt or speed up too much and self-destruct.”

The team went in search of a replacement, contacting a manufacturer who came back with a sky-high quote. But Storr’s boss at the time had another idea.

He asked whether Storr could reverse engineer a full set of governor relays. “I made the fatal mistake of saying, ‘Yeah!’ So I set off with a few photographs and a handful of sketches,” Storr explains.

What followed were sleepless nights and a lot of grey hair, but in the end he managed to reproduce a full set that cost nearly half of the original quote. Better than that, they worked perfectly.

“Today, they’re on Unit 5, doing the business.”

Building the workshop

Manufacturing the governor relays was a turning point. Storr and the team saw there could be further savings and benefits if they did more manufacturing or refurbishment in-house. They had the staff capable of doing it, they just needed the facilities.

Although there was some initial scepticism from some in the company, Drax armed Storr with a small budget and he set out on building the workshop. That was 15 years ago. Back then, the workshop was designed to only refurbish equipment, but it has since grown. Now they can manufacture, too.

Today, when Drax buys in equipment which is either very expensive or lacking in quality, Storr’s team can modify it, make it fit better, last longer, or improve its efficiency without sending it away from the plant and incurring extra costs.

“We’re reaping the rewards. We’re leagues in front of everyone else in the UK because we’ve got our own manufacturing and machining facility,” Storr says. “We can do all this work on site. We’re not relying on other people.”

The workshop has given Drax an edge when it comes to its engineering ability, but Storr remains modest about the achievement.

“The thing is,” he says, “I’ve got a good boss and he will support you. But I do see it as a bit of a feather in my cap.”

The life of an electrical engineer

Power generation
Gary Preece

A station like Drax doesn’t run itself. Its six turbines generate nearly 4,000MW of power when operating at full load. Unsurprisingly, for a site that produces 7% of Britain’s electricity needs, the role of an electrical engineer is an important one – both when managing how power is connected to the high-voltage electricity transmission grid, and how the giant electrical machines generating the energy work.

“It doesn’t get much bigger than Drax. You need to be at the top of your game, every day,” says Lead Engineer Gary Preece.

A man at the top of his game is a fair way to describe Preece. He has been an electrical engineer almost his entire life. Beginning as an apprentice working at the Liverpool dockyards at age 16, Preece has worked a range of increasingly demanding projects and roles, including engineering consultancy and work for the Royal Navy on their Type 26 Global Combat Ship, where he was in charge of designing the on-board power infrastructure.

He became a member of the Drax team five years ago.

Life on the job

“On a station the size of Drax, you don’t have a typical day. There are just too many systems that can change status, that can fail, or that require immediate attention to remain operational. It’s never-ending,” Preece says.

Working as an electrical engineer in a plant the size of Drax doesn’t just mean getting called down to help out when a fuse blows. His responsibilities as lead engineer encompass a broad range of functions.

“There’s lots to do. There’s a lot of hands-on work, but there’s also a lot of study work.” Tasks can include scoping out, planning and budgeting new projects, working with contractors and suppliers, fault analysis and power level studies.

This last role is what Preece has come to like most about the job – working with sophisticated computer simulations to model output and crisis scenarios, all so Drax can operate at its optimal level with National Grid.

“I really enjoy a lot of the theoretical work,” he says. “We can do so much with this software.”

Of course, there are times when he does have to fix things. And in a power plant, mistakes can have major consequences. “The energy levels in a power plant are so high that when something fails, it usually fails spectacularly.”

This means Preece needs to be on call all day and all night. If there’s a technology failure, he needs to be on the site, finding out what went wrong and directing recovery efforts. “There’s no hiding place. If something goes wrong, you have to fix it.”

Transforming Drax’s electric infrastructure

Sometimes individual projects can occupy all aspects of Preece: engineer, thinker and planner.

One of the most challenging was when Drax wanted to import a largely unused industrial generator transformer unit from Kent to the station in Yorkshire.

The transformer was split into three 200-tonne components. Before transit, Preece and his team conducted extensive checks on the components and oil (transformers contain oil to insulate the coil), to evaluate the state of the machinery. And these steps had to be repeated after every stage of the journey, to ensure no damage had been sustained.

After checks were completed, the units needed to be transported via the M25 motorway to ports in the south of England, from which they would travel by ship on the North Sea, ready to be unloaded and transported to Drax for installation.

However, the team hit complications, this time with the Highways Agency. “The structures were so heavy, that we had to take a ferry from a different port because authorities were worried the bridges we were planning on using to get there wouldn’t take the weight of the units. We had to do a turnaround in the middle of the motorway!”

Getting the extra transformers installed gave the plant some important breathing room in the unlikely event of a failure. “Some power stations don’t have spares. If there was a failure, they could be out of commission for months,” says Preece.

For a power station as large as Drax, that would be disastrous. But even with the extra transformers on site, the number of ways the electrical infrastructure at a power plant can go wrong is huge. That’s why experienced engineers like Preece are as indispensable as the machinery itself.

“Drax is one of the best opportunities you’re going to get for artistic licence. It doesn’t get much bigger.”

A positive negative

18 January 2017

Carbon capture
Tubes running in the direction of the setting sun. Pipeline transportation is most common way of transporting goods such as Oil, natural gas or water on long distances.

This story was updated in June 2018 following the announcement of Drax’s pilot BECCS project.

Is there a way to generate electricity not only with no emissions, but with negative emissions?

It’s an idea that, after decades of being reliant on coal had seemed almost impossible. But as Drax has shown by announcing a pilot of the first bioenergy carbon capture storage (BECCS) project of its kind in Europe, it might not be impossible for much longer.

A few years on from the historic Paris Agreement – which sets a target of keeping global temperature rise below two degrees Celsius – innovative solutions for reducing emissions are critical. Among these, few are more promising than BECCS.

It sounds like a straightforward solution – capture carbon emissions and lock them up hundreds of metres underground or turn the carbon into useful products – but the result could be game-changing: generating electricity with negative emissions.

Capturing carbon

Carbon capture and storage (CCS) technology works by trapping the carbon dioxide (CO2) emitted after a fuel source has been used and moving it to safe storage – often in depleted oil and gas reservoirs underground.

There are a number of CCS technologies available but one of the simplest is oxyfuel combustion. Fuel such as coal, gas or biomass, is burnt in a high oxygen environment and CO2 – rather than carbon (C) or carbon monoxide (CO) – is produced. Other impurities are removed and the resulting pure CO2 is compressed to form a liquid. This CO2 can then be transported via pipeline to its designated storage space, normally hundreds of metres underground.

The UK is well-placed to benefit from the technology thanks to the North Sea – which has enough space to store the EU’s carbon emissions for the next 100 years.

It’s a technology that can drastically reduce the emissions from fossil fuel use, but how can it be used to produce negative emissions?

Two technologies, working as one

Biomass, such as sustainably sourced compressed wood pellets, is a renewable fuel – the CO2 captured as part of its life in the forest is equal to the emissions it releases when used to generate electricity. When coupled with CCS, the overall process of biomass electricity generation removes more CO2 from the atmosphere than it releases.

A report published by the Energy Technology Institute (ETI) looking at the UK has suggested that by the 2050s BECCS could deliver roughly 55 million tonnes of net negative emissions a year – approximately half the nation’s emissions target.

It’s not the only body heralding it as a necessary step for the future. The Intergovernmental Panel on Climate Change (IPCC), stated in a 2014 report that keeping global warming below two degrees Celsius would be difficult if BECCS had limited deployment.

Support is widespread, but for it to lead to a practical future, BECCS needs suitable support and investment.

Morehouse BioEnergy pellet plant

Mills such as Morehouse BioEnergy manufacture compressed wood pellets – a sustainably-sourced fuel for BECCS power plants of the future.

Positive support for negative emissions

There are only a handful of CCS projects in operation or under construction across the world and many simply re-use rather than capture the CO2. Part of the reason is cost. It’s estimated that optimal CCS technology can cost about as much as the power station itself to install, and running it can consume up to 20% of a station’s power output. This means more fuel is needed to produce the same amount of power compared to a conventional power plant of similar efficiency.

Without government support, it remains a prohibitively expensive solution for many power generators. With government support in the form of multi-decade contracts, large CCS or BECCS plants could leverage economies of scale. They could deliver energy companies and their shareholders a return on the investments in the long-term.

Drax research and development

Past plans by Drax could have put the company on a timeline towards becoming the world’s first large scale negative emitter of CO2. It would have achieved it firstly with the construction of a CCS power station at its Selby, North Yorkshire site.

The 428 MW White Rose power station was to be fuelled by a mixture of coal and biomass and once in operation, could have paved the way for similar facilities elsewhere as carbon capture technology improved and costs came down, but unfortunately the project never went ahead.

There are some positive signs that carbon capture technologies are developing around the world. The first ‘clean coal’ power station became operational in the US earlier this month – and a second CCS plant is on the way. A UK-backed carbon capture and use (CCU) project in India recently opened at a chemicals factory, involving the capture of emissions for use in the manufacturing process.

Back in the UK, where the government outlined plans to end coal-fired power generation by 2025, carbon capture power stations must become financially competitive if they are to become a major part of the country’s low carbon future. But if the world is to achieve the targets agreed in Paris and pursue a cleaner future, negative emissions are a must, and BECCS remains a leading technology to help achieve it.

These three inches of copper can power a city

17 January 2017

Electrification

A series of unassuming cables extend out of the turbine hall at Drax Power Station. They’re easily missed, but these few inches of copper play an instrumental role in powering your home. Surging through each one is enough electricity to power a city.

But the process of getting electricity from power station to plug isn’t as simple as connecting one wire to a live turbine and another to your iPhone charger. We need an entire network of power stations, cables and transformers.

Linking the network

When the country first became electrified it did so in stages. Each region of the UK was powered by its own self-contained power supply. That changed in 1926 when the UK set up the Central Electricity Board and began what was at the time the biggest construction project Britain had ever seen: the national grid

The project took 100,000 men and five years to complete and when it was finished it connected 122 of the country’s most efficient power stations via 4,000 miles of overhead cabling. It had a sizeable effect. In 1920 there were roughly 750,000 electricity consumers; by 1938 that had risen to 9 million.

The grid has changed in the 80 years that’s passed, but it remains the network that transfers power across the country to where it’s needed, whenever it’s needed.

“The strange thing about electricity is that you could live 10 miles from a power station and you can’t be sure the electricity you’re using is coming from that station,” says Callan Masters, an engineer with National Grid whose job it is to maintain and upgrade the network. “The whole system works together – the whole system has a demand and the whole system has to deliver it.”

And to do this, the network has to be able to deliver electricity quickly and efficiently. Masters explains: “It acts like a motorway for power.”

High Voltage Tower on Sunset, Electric Pylon on field

Riding the motorway for power

The process of transporting electricity involves a series of stages, the first of which is ‘stepping up’ the voltage.

When electricity is transported via cables or wires it loses some of its energy as heat. Think of a lightbulb – as it illuminates it heats up because it’s losing energy. The lower the current of that electricity, however, the less energy is lost. So to reduce these losses when transporting power, National Grid transmits electricity at low currents, which it can do by increasing its voltage.

At the power station electricity is generated at 23,500 volts and is then ‘stepped up’ to 400,000 volts by a transformer. The first of these is located on a substation on site at the power station.

Once stepped up, the electricity is transported through high transmission cables – before being ‘stepped down’ via a transformer on the other end. This stepped down electricity is passed onto a regional distribution system, such as the overhead cables you might find on top of wooden poles before being stepped down a final time. “That’s the role of a little transformer at the end of your street,” Masters explains. Finally, the electricity is transported via a final cable into your home – this time at 230 volts.

All this needs to happen incredibly quickly. As thousands of kettles are switched on to herald the end of EastEnders, the demand of electricity surges. Delivering that electricity at the touch of a button relies on a complex network, but it starts with those inconspicuous few inches of copper at the power station.

Vikings, airships and ash: the history of Barlow Mound

10 January 2017

Sustainable business
Airship at Barlow Mound

Barlow Mound is a haven for wildlife. More than 100 different species call it home, including kingfishers, roe deer and falcons. It’s an area that looks like it’s never been touched by the industrialisation that surrounds it. The truth is very different.

Barlow mound is manmade. It was built in the 1970s using residue material from its neighbour Drax Power Station. It’s a success story of using what was then considered a waste material to create something natural and beautiful. But it has a long history before becoming what it is today and to explore that history is to track the outlook of the UK over the last millennium.

The military moves in

The area around Barlow and Drax was an important location for the very first Viking explorers who arrived here from the North Sea via the region’s Ouse and Aire rivers. But it wasn’t until 1086 that it received its first recorded mention, when it was listed as ‘Berlai-leag’ in the Domesday Book.

Translating to ‘a clearing where barley grew’, it was named by Anglo Saxon settlers, who established the region as a mix of farmland, fields and woodlands and it remained agricultural until the early twentieth century, when the country was plunged into war.

When the First World War began in 1914 and the need for new war machines arose, Sir W G Armstrong Whitworth & Co Ltd, a manufacturing company which had obtained the land in 1913 from the estate of Lord Londesborough, set up an airship factory on the site.

During its lifetime the factory constructed three airships, the 25r, R29 and R33, but when WWI ended and demand for airships sank, the factory shut down and the land passed to the Ministry of Defence (MOD).

During the Second World War the area became an important location in the country’s war efforts once again. The MOD set up an army ordnance and command supply depot manufacturing and storing items like mess tins and kerosene lamps. At one point the site also included a Prisoner of War camp.

By the 60s the UK’s needs for defence manufacturing had subsided. Instead, what it needed was more power. With the rich coal seams of the area and the existing rail network (the Hull-Barnsley line ran through), building a power station in the Barlow area was an obvious solution.

First-of-a-kind solution

In 1967 the land was bought by the Central Electric Generating Board (CEGB) which began the construction of Drax Power Station. One of the early challenges it faced was how to minimise the environmental impact to the surrounding countryside.

In particular, it needed a solution for the tonnes of ash that came from the burning of coal fuel, which included both pulverised fuel ash (PFA) and furnace bottom ash (FBA). The answer was a first-of-a-kind: build a mound using the materials.

Construction on Barlow Mound began in 1974. First the existing top soil was removed and preserved for later use, drains were added and then a layer of FBA was laid.

Next conditioned PFA was added and moulded to suit the original design, never reaching higher than 36 metres. At this height the mound would visually obscure the power station from the neighbouring houses.

The final step was to seal the mound with a polymer and then reintroduce the top soil before grass, trees and hedgerow were planted. The trees and plants had been carefully tested to ensure that their roots wouldn’t interfere with the ash and compromise the integrity of the structure.

Roe deer walking in grass field

An ecologically important area

As time has passed and Drax Power Station has produced more ash, the mound has developed and grown. More than 301 million m3 is stored in the current site – more than the capacity of three million double decker buses.

In addition to the 100 species living on the site, a tenant farmer works 20 fields and a swan rescue and wildlife hospital rehabilitates up to 2,000 birds a year. More recently, the Skylark Centre and Nature Reserve has now opened up the area to the public to explore walking trails and see the nature first-hand.

Barlow is an area that has changed consistently since 1086. From the North’s early beginnings as an agricultural hub and Anglo-Saxon settlement, to the necessity for large-scale power solutions and to the importance of preserving local ecology, Barlow is an area that has been characterised by the outlook of the country.

Like Drax Power Station, to which it is intrinsically linked, Barlow Mound is a part of the Northern Yorkshire landscape – literally and figuratively.

This is how smart meters will change how you use power

5 January 2017

Electrification
An on button glowing neon blue.

Homes in the UK rely on energy almost 24 hours a day. Whether powering your computer, boiling your kettle or heating your home, electricity and heating fuels are absolutely integral parts of modern life. The same is the case with businesses and transport.

But how the gas and electricity we use to power our lives is tracked, recorded and fed back to utility companies is changing. It could mean lower bills and a more stable energy network and it’s all thanks to a small, inconspicuous box called a smart meter.

What is a smart meter?

Between now and 2020, every household and business in the UK will be offered smart meters for both electricity and, where they are on the network, gas too. A smart meter is a device that tracks your energy use in real-time and then automatically feeds this information back to your energy provider.

Better yet, in the UK they’ll be coupled with an in-home display showing what you’re using and how much it’s costing. It’s a simple piece of technology that can have a serious impact on how you use energy and how much you pay for it.

Will smart meters help reduce my energy bills?

The crucial difference a smart meter will make to household bills is seeing off estimated bills. In the past, utility companies would either ask you to take a reading from your meter, or send a representative to your home or office to get one. When they’ve not been able to do this, utility companies estimate your usage within a certain time frame and create a bill based on that.

With smart meters, the automatically-delivered details will mean utility companies have up-to-the-minute accuracy on customers’ energy usage. No more estimated bills. No more searching for your awkwardly-placed meter. No more unannounced meter readers arriving at your door.

A Haven Power smart meter in use.

Will smart meters change how I use electricity?

More than just improving accuracy and saving time, smart meters can help you use energy in a … smarter way.

They can pinpoint power-heavy home appliances as well as the times of day when you are using the most energy. With this information, you can optimise your usage to find where there are cost saving opportunities.

The data collected by your smart meter might show that you use most electricity in the evening when power demand is at its highest. Based on this you can change your habits to make the most of off-peak times and potentially lower tariffs, for example charging your battery-based appliances overnight.

Are smart meters good for the UK?

More accurate information is not only a benefit to home and business owners – the country as a whole could end up in a better place, too.

Armed with accurate numbers on how and when the country uses power, the National Grid, which manages the gas and high voltage electricity network, and Elexon, which manages the balancing market for electricity, will be able to better predict energy supply. If they track that electricity is being used at a certain time of day they can ensure generation by UK power stations like Drax, the UK’s biggest, is planned to match it. The aim is a more stable and efficient grid.

Utility companies could also use this data to create peak and off-peak times with different tariffs, opening the door for further cost savings and the smarter use of electricity nationwide. Coupled with the new market in battery technology such as the PowerVault and Tesla’s PowerWall 2, households and businesses will also be able to take even greater advantage of off-peak tariffs.

How can I get a smart meter?

Your electricity or heat supplier may install it for you, depending on the deal or package you are on. Contact them to find out what options are available.

Drax’s own electricity supplier, Haven Power, is currently investing in technology to allow it to use the new national smart metering infrastructure. It will begin rolling out smart meters to its customers during 2017 and will offer them to all of the businesses that purchase electricity from Haven Power by 2020.

Billington Bioenergy, Drax’s supplier of compressed wood pellets for heat, has installed smart meters – known as fuel level measurement systems – across various industries such as Care Home sector and Schools and projects that a third of its bulk-blown pellet customers will have them installed by 2020.

Your Christmas lights were powered by more renewables than ever before

29 December 2016

Electrification
A single strand of Icicle Christmas Lights.

Late into the evening of Christmas Day, 2016, millions of people sat down to watch Rowan Atkinson solve a grisly murder. It was the TV drama Maigret’s Dead Man, and although it wasn’t the most watched TV show on Christmas Day (that honour went to the Strictly Come Dancing finale), it did cause the biggest television-related sudden surge in electricity demand of the day, says Sumit Gumber, Energy Forecasting Analyst at National Grid.

During a critical ad break in the show, demand jumped 400 MW – roughly equivalent to 160,000 kettles being switched on – as viewers raced to make cups of tea or go to the bathroom. This is known as a TV pickup.

While this may have provided the biggest sudden rise in electricity usage of the day, it was not the overall peak. As is typical on Christmas Day, this year’s spike in demand came just before one o’clock, when families were preparing their festive feasts.

At 37.1 GW, this peak was not only lower than previous years, the power used to supply it was generated by more renewables than any Christmas before it. More than 40% of the electricity generated on Christmas Day came from renewable sources.

What characterises Christmas day?

Christmas is a day when electricity usage is at one of its lowest points. To put this year’s 37.1 GW peak into context, an average weekday during December (weekday electricity use is higher than on weekends) has an electricity peak of nearly 50 GW, usually occurring between five and seven o’clock, when people arrive home and street lighting is switched on.

The cause for the lower demand during Christmas is simple – over the festive period schools, as well as a number of offices, shops and factories are closed.

Over the last few years average Christmas Day demand has been fairly typical, sitting in a bracket of between 29 GW and 39 GW. In 2010, however, extreme cold (hitting minus three degrees Celsius) drove lunchtime peak demand as high as 46 GW, showing just how important a driver of our electricity use temperature is.

But while demand on Christmas in 2016 may not have deviated largely from the average over the last few years, there were some major leaps forward in how it was generated.

Winter landscape with wind turbines

A greener Christmas than ever before

This year, Christmas was characterised by a huge jump in renewable electricity generation.  On average, 12.4 GW came from renewable sources – more than ever before. Of that figure, wind contributed the most, generating on average 9.4 GW – equivalent to 31% of all power supplied on Christmas Day.

Compared to 2015 it’s a 63% increase and a staggering 195% uplift from five Christmases ago in 2012 when just 12% of all electricity generated came from renewable sources. Biomass generation has also increased, providing 2 GW in 2016 compared to the 0.5 GW it averaged on December 25th, 2012.

The increase in renewables also marks an important step towards decarbonisation: at its peak, emissions from electricity generation this 25th December were just 168 g/kWh, a significant drop compared to the 2012 peak of 506 g/kWh and the 303 g/kWh seen in 2015.

This year has been a year of impressive stats in clean energy: between July and September, for the first time in its 130-year-old history, more than half of Britain’s power came from low-carbon sources; on 5th May the UK did not burn any coal to generate electricity, the first time since 1881. Now, we’ve seen one of the cleanest Christmases on record. It’s a Christmas tradition that is likely to continue.

Biggest TV pick-ups, Christmas Day 2016

 

  1. Maigret’s Dead Man and EastEnders (22:30) – 400 MW (equivalent to 160,000 2.5 kW kettles switched on)

  2. Paul O’Grady: For the Love of Dogs at Christmas (19:45) – 275 MW (110,000 kettles)

  3. The Great Christmas Bake Off  (17:45) – 210 MW (84,000 kettles)

  4. Emmerdale and Doctor Who (18:45) – 200 MW (80,000 kettles)

Thanks to National Grid for this data

Explore how Britain was powered over the festive period by visiting electricinsights.co.uk.

Power and the rise of electric cars

12 December 2016

Electrification
Power supply for electric car charging. Electric car charging station. Close up of the power supply plugged into an electric car being charged.

All great technological innovations need infrastructure to match. The world didn’t change from candles to lightbulbs overnight – power stations had to be built, electricity cables rolled out, and buildings fitted with wiring. The same is true of electric vehicles (EV).

Think of the number of petrol stations lining the UK roads. If EVs continue their rise in popularity, the country will need electric car-charging facilities to augment and then replace these petrol stations.

This could mean big extensions of electricity grid infrastructure, both in the building of new power generation capacity to meet demand, and in the extension of the networks themselves.

In short, it could mean a significant change in how electricity is used and supplied.

The need for better electricity infrastructure

In 2013, only 3,500 of newly registered cars in the UK were plug-in electric or hybrid EVs. In 2016, that number jumped to 63,000. Their use is rising rapidly, but the lack of infrastructure has kept a cap on the number of EVs on UK roads. That is starting to change.

As of 2019, all new and refurbished houses in the EU will have to be fitted with an electric car charging point, according to a draft directive announced by Brussels. The UK will probably no longer be an EU member by the time the directive comes into effect, but nevertheless, the UK government is pursuing its own ways to account for the rise of EVs. It has pledged more than £600 million between 2015 and 2020 to support ultra-low-emission vehicles – £38 million of this has already been earmarked for public charging points.

There are more innovative responses to EV rise, too. Nissan, in partnership with Italian energy provider Enel, has announced it will install around one hundred ‘car-to-grid’ charging points across the UK. With their innovative V2G technology, cars plugged into these sites will be able to both charge their batteries and feed stored energy back to the National Grid when necessary. So when there is a peak in demand, the Grid could access the cars’ stored energy to help meet it.

The total capacity of the 18,000 Nissan electric vehicles currently operational on UK roads comes to around 180 MW. So even today – before electric vehicles have really taken off – this could give the National Grid an additional supply roughly the size of a small power station.

Peaks in electricity demand, however, tend to occur in the late afternoon or evening as it gets dark and more lighting and heating gets switched on. This also happens to be rush hour, so under this scheme the time of day the cars are most likely to be on the roads is also when it’d be most helpful to have them plugged in. This could lead to financial incentives for people to give up the flexibility of driving their cars only when they need to.

Power supply for electric car charging. Electric car charging station.

More electric cars, more demand for electricity, more pollution?

More EVs on the road makes sound environmental sense – they enable a 40% reduction in CO2 emissions – but ultimately the energy still has to come from somewhere. That means more power stations.

The scale of this new demand shouldn’t be underestimated: if European drivers were to go 80% electric, some studies have suggested it would require 150 GW of additional on-demand capacity – the equivalent of 40 Drax-sized power stations.

But if EVs are to live up to their green potential, that additional power needs to come from innovations in storage (such as in the Nissan example) and from renewable sources like wind, solar and biomass. Fossil fuels would ideally be used only to plug any gaps that intermittency creates – for example by briefly firing up the small gas power stations Drax plans to build in England and Wales.

What does this mean for generators?

Drax, as operator of the UK’s largest biomass power station and with plans for new, rapid response open cycle gas turbines (OCGTs), is well placed to be at the forefront of providing reliable, affordable power in the event of a widespread rollout of electric vehicles. The OCGTs in particular, are designed for use in peak times which, in the future, could be when the nation’s electric vehicles are plugged in overnight – today this is when electricity demand is at its lowest.

A future of more electric cars is a positive one. They’re cleaner, more efficient, and they are well suited to our increasingly urban lives. But now that we have the technology, we need to ensure we can deliver the lower-carbon infrastructure they need.

Some like it hot: how temperature affects electricity prices

30 November 2016

Electrification
misty-british-county-landscape

In 2012, Europe faced an extreme cold wave. Temperatures in France dropped to minus four degrees Celsius, far below its average of five above.

As people huddled indoors, electric heaters were dialled up and lights were switched on. Electricity demand soared. It topped at 102 GW, surpassing the country’s previous peak by more than 20 GW. France had to import power from neighbouring countries.

The low temperatures drove demand so high the country couldn’t manage on its own. It’s something we see across the world – temperature peaks drive how and when we use electricity, increasing demand in the colder Northern European countries as the temperature falls, and acting inversely in hotter Southern countries.

But more than just driving up how much electricity we need, the temperature can affect how much we pay for it, too.

Putting a price on electricity

In the UK electricity is bought and sold by power generators, energy suppliers and the National Grid by the megawatt hour (MWh). One MWh is roughly enough power to boil 400 kettles and although prices fluctuate significantly, on average one MWh costs roughly £50 in the UK. In winter, when UK electricity demand peaks it’s estimated that for every degree the temperature drops below 15 Celsius, demand rises by 820 MW.

Electric Insights, an independent report produced by researchers at Imperial College London and commissioned by Drax via Imperial Consultants, looks at the UK’s publicly available electricity data and clearly shows the trend.

Electricity demand, temperature and prices

As the temperature drops, demand rises.

This raised demand affects the price of electricity in one obvious way: consumers’ bills rise because they’re using more of it. A less obvious impact is its effect on the production and supply cost of electricity from generator to the high voltage electricity transmission grid.

How temperature affects supply

In cold weather power plants work better. Cooling towers are more efficient, power cables are more conductive, and less energy is needed to help keep generating equipment from overheating. This all adds to small cost savings, which in turn can make electricity cheaper.

However, during colder weather the amount of gas used in the UK goes up – largely due to the rise in heating – which raises its price and this has a knock effect on electricity. For every 1p increase in the cost of gas, the cost of generating 1 MWh by a CCGT (combined cycle gas turbine) power station increases by around 70p. As CCGTs generate a large percentage of Britain’s electricity, the overall price of electricity also goes up.

But a bigger cost-determining factor is the increasing variety in today’s energy make up. Renewables like wind and solar are intermittent energy sources. Solar can’t function at night or when it’s overcast; wind turbines don’t rotate when it’s still, so when it is especially cold, dark or without much wind, the Grid needs to bring in additional flexible power generated by sources like biomass, gas and coal. These technologies can either deliver power to the Grid all the time – known as baseload – or just when demand rises, when they can be dialled up quickly.

But in the event of extreme weather, the demand for power can surge and the Grid needs to bring in additional generation capacity. In Britain, there are smaller power stations fuelled by diesel, oil or gas that lie dormant for much of the year but can start up at short notice to provide this boost of generation to meet demand.

Activating and running these plants quickly for short amounts of time can be expensive, and this can subsequently affect electricity price and lead to spikes in the winter.

Pylons in the countryside with the sun behind themThe effect on the bottom line

This leads to the following trend: for every degree Celsius the temperature falls below 10, there is a corresponding rise of £1.10 MWh. It is also possible for increases in temperature to cause increased prices, but this is usually in countries where air conditioners and electrically-powered cooling units are hooked up to their own national or regional electricity grid. For better or worse, this is not a problem that affects the UK, but it’s important to understand that maintaining grid stability will always have its costs, whatever the weather.