Tag: electricity

How getting renewable energy from your supplier actually works

2 April 2019

Sustainable bioenergy

Where does our electricity come from? One answer might be the power stations, wind turbines and solar panels that generate it. You might even go as far as to say the wind, sun, water, biomass and gas powering those stations. Or even the network companies transporting that power around the country. But there’s also a very important middle-man in this process: electricity suppliers.

Most of Great Britain gets its power from one of the ‘Big Six’ energy suppliers, which buy electricity from the wholesale market and then sells it to consumers. However, with more businesses and consumers looking for less carbon-intense electricity sources, there are now a whole host of smaller companies taking on the incumbents and offering all-renewable electricity.

From Ovo to Bulb to Drax’s own Haven Power and Opus Energy, consumers and businesses have more and greener options than ever about where to buy their electricity, with many even offering 100% renewable electricity.

But how do these companies ensure the megawatts powering homes, offices and street lights come from renewable sources?

Cleaning up the river

The electricity we use doesn’t just flow through a single cable from a power station to our houses. It travels through what’s called the transmissions system, which is run by National Grid ESO and local distribution network operators.

Apart from off-grid installations like solar panels on buildings, some of which are unable to export their unused power, all the electricity generated by different sources around the country goes into this same system. It means megawatts generated by a wind turbine get mixed up with those generated by a nuclear reactor or a coal power station.

Think of it as a river. Although it is its own entity, it is fed by multiple streams of water coming from different sources. In the case of electricity, megawatts from various generators are fed into a central system, which then enter homes, offices and devices around the country.

So, what makes green power generated from renewable sources, green power used in homes?

Suppliers can’t control exactly what megawatts you use, but they can influence the makeup of the overall ‘river’ your electricity is pulled from by what electricity they agree to buy and offer to their customers.

Renewable suppliers match the amount of electricity their customers use with the amount they buy from renewable sources. So, if a home uses 4 megawatt-hours (MWh) a year, a supplier will need to ensure it buys an equal amount of power from National Grid, which National Grid sources from generators. If that supplier offers 100% renewable power, it will need to ensure it has the right kinds of deals in place with renewable generators to deliver that amount of power.

It means that while the river of electricity is still a mix from different streams, more of the water will come from renewable streams. Therefore, if more homes and businesses switch to renewable suppliers, more of the overall river will be renewable, which will in turn help to decarbonise the electricity system, enabling a lower-carbon economy.

But how does this fit into the existing electricity business and infrastructure?

But how do suppliers actually buy renewable power from generators?

The business of electricity

To understand how suppliers ensure they are buying renewable power you first need to understand how the business works. Or at least, how it used to. The most obvious place to start is with the generators.

Be they gas power stations or an offshore wind farm, the generator is where electricity is produced and are often owned by a supplier.

Suppliers can buy electricity from their own generators, often months or years ahead of delivery. But if there is a shortfall, the supplier can also buy electricity on the wholesale market, where other generators can sell their electricity.

Because suppliers are on a competitive market, their aim is to buy the electricity for the lowest possible price and sell it for more – but at a better rate than rivals. Measures like carbon prices or green incentives help lower the cost of renewable and low-carbon generation, and position it as a more economically viable purchase than more expensive fossil fuels like coal.

Renewable-only suppliers also want to buy electricity as cheap as possible and sell it as affordably as possible. But unlike standard suppliers they only buy electricity from renewable sources.

This can be done by purchasing electricity from independent renewable generators on the wholesale market, or arranged through what are known as Power Purchase Agreements (PPAs) – longer-term contracts between generators and suppliers agreeing on a specific amount of power.

The advantage of these for the renewable generator is it secures revenue for the future, while for the supplier it means a dependable source of electricity. For large installations, these deals are often signed before construction even begins to ensure investors there will be a return.

Transitioning to a low-carbon electricity system, however, is not just about suppliers buying more electricity from renewable sources.

The future of electricity suppliers

As more businesses, individuals and communities are becoming prosumers and generating their own electricity, the wider role of the supplier in the system is changing.

The government’s feed-in-tariffs financially reward customers for generating their own electricity, even if they don’t export it to the grid. But even small generators can sign deals with suppliers to sell electricity through schemes such as Good Energy’s SmartGen policy, which is open to generators with between 10 and 100 kilowatts (kW) of installed capacity. Similarly Opus Energy helps over 2,100 businesses sell more than 1,100 gigawatt-hours (GWh) of excess wind, solar, anaerobic digestion and hydro power.

For larger prosumer businesses, the relationship with suppliers and the grid is different. Rather than the traditional buying and selling of electricity, it requires a cooperative approach to understand how the prosumer can best utilise their assets.

Beyond increasing the amount of low-carbon electricity, decarbonising the electricity system also means making more efficient use of energy and managing the data that can help improve efficiency. Haven Power’s partnership with Thames Water sees it analyse an average of 68 million half-hour smart meter readings every year, using the data to help the company improve its billing and forecasting. As the wider system becomes more intelligent, suppliers will be able to better forecast how much electricity its customers use and help them reduce their consumption.

The role required of suppliers in a changing system will create opportunities for more renewable and efficient use of electricity. And empower more consumers to get their electricity from low-carbon sources that can help to make the whole country’s electricity greener.

Want a different perspective on the same story? Watch TV’s Jonny Ball explain.

Can Great Britain keep breaking renewable records?

15 February 2019

Power generation

How low carbon can Britain’s electricity go? As low as zero carbon still seems a long way off but  every year records continue to be broken for all types of renewable electricity. 2018 was no different.

Over the full 12-month period, 53% of all Britain’s electricity was produced from low carbon sources, which includes both renewable and nuclear generation, up from 50% in 2017.  The increase in low carbon shoved fossil fuel generation down to just 47% of the country’s overall mix.

The findings come from Electric Insights, a quarterly report commissioned by Drax and written by researchers from Imperial College London.

The report found electricity’s average carbon intensity fell 8% to 217 grams of carbon dioxide per kilowatt-hour of electricity generated (g/kWh), and while this continues an ongoing decline that keeps the country on track to meet the Committee on Climate Change’s target of 100 g/kWh by 2030, it was, however, the slowest rate of decline since 2013.

It also highlights that while Britain can continue to decarbonise in 2019, the challenges of the years ahead will make it tougher to continue to break the records it has over the past few years.

The highs and lows of 2018

Last year, every type of renewable record that could be broken, was broken. Wind, solar and biomass all set new 10-year highs for respective annual, monthly and daily generation, as well as records for instantaneous output (generation over a half-hour period) and share of the electricity mix. The result was a new instantaneous generation high of 21 gigawatts (GW) for renewables, 58% of total output.

Wind had a particularly good year of renewable record-setting. It broke the 15 GW barrier for instantaneous output for the first time and accounted for 48% of total generation during a half hour period at 5am on 18 December.

Overall low carbon generation, which takes into account renewables and nuclear (both that generated in Britain and imported from French reactors), had an equally record-breaking year with an average of almost 18 GW across the full year and a new record for instantaneous output of 30 GW at 1pm on 14 June – nearly 90% of total generation over the half hour period.

While low carbon and individual renewable electricity sources hit record highs, there were also some milestone lows. Coal accounted for an average of just 5% of electricity output over the year, hitting a record low in June, when it made up just 1% of that month’s total generation. Fossil fuel output overall had a similarly significant decline, hitting a decade-low of 15 GW on average for 2018 – 44% of total generation over the year.

One fossil fuel that bucked the trend, however, was gas, which hit an all-time output of 27 GW for instantaneous generation on the night of 26 January. There was low wind on that day last year, plus much of the nuclear fleet was out of action for reactor maintenance. In one case, with seaweed clogging a cooling system.

This was all aided by an ongoing decline in overall demand as ever smarter and more efficient devices helped the country reach the decade’s lowest annual average demand of 33.5 GW. More impressive when considering how much the country’s electricity system has changed over the last decade, however, is the record low demand net of wind and solar. Only 9.9 GW was needed from other energy technologies at 4am on 14 June.

How the generation mix has changed

The most remarkable change in Britain’s electricity mix has been how far out of favour coal has fallen. From its position as the primary source from 2012 to 2014, in the space of four years it has crashed down to sixth in the mix with nuclear, wind, imports, biomass and gas all playing bigger roles in the system.

 

This sudden decline in 2015 was the result of the carbon price nearly doubling from £9.54 to £18.08 per tonne of carbon dioxide (CO2) in April, making profitable coal power stations loss-making overnight. With coal continuing to crash out of the mix, biomass has become the most-used solid fuel in Britain’s electricity system.

Interconnectors are also playing a more significant part in Britain’s electricity mix since their introduction to the capacity market in 2015. Thanks to increased interconnection to Europe, Britain is now a net importer of electricity, with 22 TWh brought in from Europe in 2018 – nine times more than it exported.

While more of Britain’s electricity comes from underwater power lines, less of it is being generated by water itself. Hydro’s decline from the fifth largest source of electricity to the eighth is the most noticeable shift outside coal’s slide. New large-scale hydro installations are expensive and a secondary focus for the government compared with cheaper renewables.

Hydro’s role in the electricity mix is also affected by drier, hotter summers, which means lower water levels. For solar, by contrast, the warmer weather will see it play a bigger role and it’s expected to overtake coal in either 2019 or 2020.

What is unlikely to change in the near-future, however, is the position at the top. In 2018 gas generated 115 TWh – more than nuclear and wind combined. But this is just one constant in a future of multiple moving and uncertain parts.

2019: a year of unpredictability

Britain is on course to leave the EU on 29 March. The effects this will have on the electricity system are still unknown, but one influential factor could be Britain’s exit from the Emissions Trading Scheme (ETS), the EU-wide market which sets prices of carbon emitted by generators. This may mean that rather than paying a carbon price on top of the ETS, as is currently the case, Britain’s generators will only have to pay the new, fixed carbon tax of £16 per tonne the UK government says will come into play in April, topped up by the carbon price support (CPS) of £18/tonne.

Lower prices for carbon relative to the fluctuating ETS + CPS, could make coal suddenly economically viable again. The black stuff could potentially become cheaper than other power sources. This about-turn could cause the carbon intensity of electricity generation to bounce up again in one or more years between 2019 and 2025, the date all coal power units will have been decommissioned.

The knock-on effect of lower carbon prices, combined with fluctuations in the Pound against the Euro, could see a reverse from imports to exports as Britain pumps its cheap, potentially coal-generated, electricity over to its European neighbours. That’s if the interconnectors can continue to function as efficiently as they do at present, which some parties believe won’t be the case if human traders have to replace the automatic trading systems currently in place.

Sizewell B Nuclear Power Station

A reversal of importing to exporting could also reduce the amount of nuclear electricity coming into the country from France. Future nuclear generation in Britain also looks in doubt with Toshiba and Hitachi’s decisions to shelve their respective plans for new nuclear reactors, which could leave a 9 GW hole in the low-carbon base capacity that nuclear normally provides.

Renewables have the potential to fill the gap and become an even bigger part of the electricity system, but this will require a push for new installations. 2018 saw a 60% drop in new wind and solar installations and less than 2 GW of new renewable capacity came onto the system, making it the slowest year for renewable growth since 2010.

Britain’s electricity has seen significant change over the last decade and 2018 once again saw the country take significant strides towards a low carbon future, but challenges lie ahead. Records might be harder to break, but it is important the momentum continues to move towards renewable, sustainable electricity.

Explore the quarter’s data in detail by visiting ElectricInsights.co.uk. Read the full report.

Commissioned by Drax, Electric Insights is produced, independently, by a team of academics from Imperial College London, led by Dr Iain Staffell and facilitated by the College’s consultancy company – Imperial Consultants.

‘3D’ to drive an energy revolution

Jonathan Kini, CEO Customers

1 February 2019

Opinion

Think of the phrase ‘3D’ and may people instantly think of video games, television or cinema, along with the special glasses you needed to watch it.

But another form of 3D is, I believe, going to be at the heart of the energy revolution which is rapidly gathering place.

The three Ds in this case are Data, Diversification and Decarbonisation. Together, they will transform the way businesses buy, use and sell their energy, help companies take control of their energy use and save money and also play a key part in our journey towards a zero carbon, lower cost energy future.

We’re already seeing some real innovations in the energy sector. Our trial of a storage battery with a customer of Opus Energy is an example, offering a farming business in Northampton the chance to sell stored energy generated by solar panels back to the grid at times of peak demand – a potential new revenue stream.

But other innovations and advances will maintain the pace of change and data will be at the core of this now the new generation of smart meters are being installed in businesses, revolutionising customer relationships with their energy suppliers.

The data from the new meters will finally give customers insight into where and when they use energy. Suppliers will have to work much more closely with customers to help them access new opportunities for cost savings, access to new markets and even new revenue streams.

An example would be a restaurant. With the data smart meters will provide, the restaurant’s supplier will be able to tell the owners how their energy use compares to the local competition and where improvements can be made.

The detail could go as far as identifying whether the restaurant’s equipment is older and less efficient, whether rivals have installed newer kit or whether other businesses are switching off their equipment earlier or using it at different, cheaper times.

Using energy during the peak weekday morning and early evening hours is often the most expensive time to do so. Data will give businesses the insight into how they can use energy more efficiently and when they use it, offering them the chance to avoid buying at peak times whenever possible and driving efficiencies.

This is why Haven Power’s trading team is now working closely with GridBeyond. The partnership allows our customers to trade the power they produce as well as optimise their operations to help balance the grid at times of peak demand. The really smart thing is that in doing so, customers are reducing their energy costs and making their operations more sustainable.

Trading desks at Haven Power’s Ipswich HQ

The way demand changes and is managed by businesses and consumers on a diversified power system will also be key. The business energy sector is already diversifying as many customers are able to generate and store their own power but the next step is for more customers to be paid to reduce their usage at peak times.

Think of a busy time for the National Grid – half time in the FA Cup Final or after the results in Strictly Come Dancing. Previously, the grid would have to pay a power station to ramp up generation to meet demand but these days, customers are paid to reduce demand for 30 minutes or so – in effect becoming a huge virtual power station.

This has happened for some time of course with larger, industrial customers but now, smaller companies can benefit from this too, thanks to the data and insight they will have from their smart meters. This empowers customers and puts them, not the energy companies, in control of the key decisions about their energy.

A close, advisory relationship between energy suppliers and their customers will become ever more important to make sure business can choose to avoid the high demand periods, and maximises use during the lower, cheaper times. In fact, I can see a time when customers will end up paying more for insight and advice than they do for the power they buy – and they’ll save money overall in doing so.

And if we get all this right, it will help drive one of the most important of the three Ds – decarbonisation.

Sustainability is increasingly becoming a primary focus for businesses and demand for renewable energy is growing because it is now cost-effective. That will help us in our drive towards a zero carbon future as more and more renewable energy comes onstream, though the UK will continue to need power generated from more flexible assets as well.

So there are huge opportunities out there to transform our energy landscape but they have to be viewed positively. The smart metering programme can be viewed as a regulatory burden or it can be seen as an opportunity. We take the positive view.

Likewise, batteries were once the preserve of massive companies only but now, as technology develops, they are becoming available for smaller firms too. The more we can innovative on a larger scale, the more the technology will work its way into smaller markets too, adding momentum to the energy revolution.

The opportunities are huge. If we get it right, so too will be the benefits to one of the biggest priorities of all – the work to decarbonise the UK and create the lower carbon future we all want.

Electricity and magnetism: the relationship that makes the modern world work

30 January 2019

Power generation

Locked in a Parisian vault and stored in a double set of bell jars is a small cylinder of metal. Made of platinum-iridium, the carefully guarded lump weighs exactly one kilogram. But more than just weighing one kilogram, it is the kilogram from which all other official kilograms are weighed.

International prototype kilogram with protective double glass bell

Known as the International Prototype Kilogram, or colloquially as Le Grand K, the weight was created in 1889 and has been carefully replicated to offer nations around the world a standardised kilogram. But over time Le Grand K and its clones have slightly deteriorated through wear and tear, despite extremely careful use. In an age of micro and nanotechnology, bits of metal aren’t quite accurate enough to dictate global weighs and so as of May this year it will no longer be the global measurement for a kilogram. An electromagnet is part of its replacement.

An electromagnet is effectively a magnet that is ‘turned on’ by running an electric current through it. Cutting the current turns it off, while increasing or decreasing the strength of the current increases and decreases the power of the magnet.

It can be used to measure a kilogram very precisely thanks to something called a Kibble Balance, which is essentially a set of scales. However, instead of using weights it uses an electromagnet to pull down one side. Because the electric current flowing through the electromagnet can be increased, decreased and measured very, very accurately, it means scientists can define any weight – in this case a kilogram – by the amount of electrical current needed to balance the scale.

This radical overhaul of how weights are defined means scientists won’t have to fly off to Paris every time they need precise kilograms. Beyond just replacing worn-out weights, however, it highlights the versatility and potential of electromagnets, from their use in electricity generation to creating hard drives and powering speakers.

The simple way to make a magnet

Magnets and electricity might at first not seem closely connected. One powers your fridge, the other attaches holiday souvenirs to it. The former certainly feels more useful. However, the relationship between magnetic and electric fields is as close as two sides of the same coin. They are both aspects of the same force: electromagnetism.

Electromagnetism is very complicated and there’re still aspects of it that are unknown today. It was thinking about electromagnetism that led Einstein to come up with his theory of special relativity. However, actually creating an electromagnet is relatively straightforward.

All matter is made up of atoms. Every neutral atom’s core is made up of static neutrons and protons, with electrons spinning around them. These electrons have a charge and a mass, giving the electrons a tiny magnetic field. In most matter all atoms are aligned in random ways and effectively all cancel each other out to render the matter non-magnetic. But if the atoms and their electrons can all be aligned in the same direction then the object becomes magnetic.

A magnet can stick to an object like a paperclip because its permanent magnetic field realigns the atoms in the paperclip to make it temporarily magnetic too – allowing the magnetic forces to line up and the materials to attract. However, once the paper clip is taken away from the magnet its atoms fall out of sync and point in random directions, cancelling out each other’s magnetic fields once again.

Whether a material can become magnetic or not relies on a similar principal as to whether it can conduct electricity. Materials like wood and glass are poor conductors because their atoms have a strong hold over their electrons. By contrast, materials like metals have a loose hold on their electrons and so are good conductors and easily magnetised. Nickle, cobalt and iron are described as ferromagnetic, because their atoms can stay in sync making them a permanent magnet. But when magnets really become useful is when electricity gets involved.

Putting magnets to work

Running an electric current through a material with a weak hold on its electrons causes them to align, creating an electromagnetic field. Because of the relationships between electric and magnetic fields, the strength of the electromagnet can also be altered by increasing or decreasing the current, while switching the flow of the current will flip its north and south poles.

Having this much control over a magnetic field makes it very useful in everyday life, including how we generate electricity.

Find out how we rewind a generator core in a clean room at the heart of Drax Power Station

Inside each of the six generator cores at Drax Power Station, is a 120-tonne rotor. When a voltage is applied, this piece of equipment becomes a massive electromagnet. When steam powers the turbines to rotate it at 3,000 rpm the rotor’s very powerful magnetic field knocks electrons in the copper bars of the surrounding stator out of place, sending them zooming through the metal, in turn generating an electrical current that is sent out to the grid. The 660 megawatts (MW) of active power Drax’s Unit 1 can export into the national transmission system is enough to power 1.3 million homes for an hour.

Beyond just producing electricity, however, electromagnets are also used to make it useful to everyday life.  Almost anything electric that depends on moving parts, from pumping loud speakers to circuit breakers to the motors of electric cars, depend on electromagnets. As more decarbonisation efforts lead to greater electrification of areas like transport, electromagnets will remain vital to daily life into the future.

The small devices that use lots of power and the big buildings that don’t

23 January 2019

Electrification

When Texas Instruments set about attempting to create the world’s first handheld calculator in the early sixties, it estimated that such a complicated device might require a battery as big and powerful as a car’s.

With some innovative thinking, the team were eventually able to power the device with just a five-volt battery, turning the calculator into a truly handheld device and kickstarting an electronics efficiency revolution. Continuous advances in the space mean that today’s super-powered smartphones run on more efficient, powerful – and smaller – sources than ever before.

But as more of our devices become ‘smart’ and grow in usage, their electricity demand is also increasing. On the other hand, many bigger objects that traditionally have used a lot of power are becoming more efficient and consuming less electricity than before.

The small devices eating up electricity

Think of the most electricity-intensive appliance in a home. Something constantly running like a fridge-freezer might come to mind – or something intensive that operates in short blasts like a hairdryer or kettle.

However, a surprising drain of electricity in homes is TV set-top boxes and consoles, which as recently as 2016 were reported to account for as much as half of all electricity usage by domestic electronics. This is because of how often they are left in standby mode, which means they are constantly using a small amount of electricity.

In 1999 the International Energy Agency (IEA) introduced the One Watt Initiative, which led to the electricity consumption of many devices on standby falling from around five watts to below one watt. And while this has helped reduce standby or ‘vampire power’, multiplied across the country – the electricity consumption becomes significant (in the UK there are an estimated 27 million TVs).

This is not just a TV-specific problem, however, it is symptomatic of many of the modern devices increasingly found in our homes, from smart lightbulbs to Amazon’s Alexa. These are constantly using small amounts of electricity, listening and connecting to the cloud even when not being directly used.

In 2014 the IEA estimated that by 2020 these networked-devices could result in $120 billion in wasted electricity. Adding to this is the increasing demand of the cloud and data storage, which has been estimated could account for 20% of the world’s electricity consumption by 2025.

Previous alarm bells surrounding the bitcoin network’s electricity usage highlights that it’s not just physical, connected objects that will put increasing pressure on electricity supply, but also entirely digital products.

Yet even as little things become smarter and require more electricity, some big things that have previously consumed huge amounts of electricity are becoming more efficient.

The big things becoming more efficient   

Buildings are a big source of electricity demand globally. Office blocks full of lights and blasting heating and air-conditioning units are among the main offenders, but poorly insulated homes that leak heat also have a significant impact.

Efforts are constantly being undertaken to reduce this via technological means such as companies generating their own electricity onsite from installed renewables. But cutting interstitial demand to a minimum doesn’t always have to be hi-tech.

The Bullitt Centre in Seattle is a 50,000 ft2office aiming to be ‘the greenest commercial building  in the world’. This is achieved in part through a rooftop solar array that allows the building to generate more electricity than it consumes, but is complimented by more straightforward steps such as maximising natural light and ventilation, collecting rainwater, and the use of geothermal heat pumps. On average the building consumes 230,000 kilowatt-hours (KWh)/year compared to the average of 1,077,000 KWh/year for Seattle offices.

Retrofitting can also make notable reductions to energy usage and New York art-deco icon, the Empire State Building, has been updated to consume 40% less electricity. This is largely thanks to straightforward renovations such as ensuring windows open properly and temperatures can be easily controlled.

Energy efficiency is even extending beyond the confines of the planet. The International Space station only consumes about 90 kW to run, which comes from a solar array stretching more than 2,400m2. When its solar panels are operational about 60% of their generation is used to refill batteries for when the station is in the Earth’s shadow.

The Mars Desert Research Station (MDRS) in Utah

Technology like this will be essential if humans are going to put buildings on other planets where we will not have vast electricity generation and transmission systems we enjoy on earth. And if that is the ambition, continuously striving for ever more efficient devices on a smarter power grid is only going to help progress us further.

The renewable pioneers

18 January 2019

Power generation

People love to celebrate inventors. It’s inventors that Apple’s famous 90s TV ad claimed ‘Think Different’, and in doing so set about changing the world. The renewable electricity sources we take for granted today all started with such people, who for one reason or another tried something new.

These are the stories of the people behind five sources of renewable electricity, whose inventions and ideas could help power the world towards a zero-carbon future.

The magician’s hydro house

Water wheel by the side of the trail to the Power House at Cragside, Rothbury, Northumberland

Using rushing rivers as a source of power dates back centuries as a mechanised way of grinding grains for flour. The first reference to a watermill dates from all the way back to the third century BCE.

However, hydropower also played a big role in the early history of electricity generation – the first hydroelectric scheme first came into action in 1878, six years before the invention of the modern steam turbine.

What important device did this early source of emissions-free electricity power? A single lamp in the Northumberland home of Victorian inventor William Armstrong. This wasn’t the only feature that made the house ahead of its time.

Water pressure also helped power a hydraulic lift and a rotating spit in the kitchen, while the house also featured hot and cold running water and an early dishwasher. One contemporary visitor dubbed the house a ‘palace of a modern magician’.

The first commercial hydropower power plant, however, opened on Vulcan Street in Appleton, Wisconsin in 1882 to provide electricity to two local paper mills, as well as the mill owner H.J. Rogers’ home.

After a false start on 27 September, the Vulcan Street Plant kicked into life in earnest on 30 September, generating about 12.5 kilowatts (kW) of electricity. It was very nearly America’s first ever commercial power plant, but was beaten to the accolade by Thomas Edison’s Pearl Street Plant in New York which opened a little less than a month earlier.

The switch to silicon that made solar possible

When the International Space Station is in sunlight, about 60% the electricity its solar arrays generate is used to charge the station’s batteries. The batteries power the station when it is not in the sun.

For much of the 20thcentury solar photovoltaic power generation didn’t appear in many more places than on calculators and satellites. But now with more large-scale and roof-top arrays popping up, solar is expected to generate a significant portion of the world’s future energy.

It’s been a long journey for solar power from its origins back in 1839 when 19-year old aspiring physicist Edmond Becquerel first noticed the photovoltaic effect. The Frenchman found that shining light on an electrode submerged in a conductive solution created an electric current. He did not, however, have any explanation for why this happened.

American inventor Charles Fritts was the first to take solar seriously as a source of large-scale generation. He hoped to compete with Thomas Edison’s coal powered plants in 1883, when he made the first recognisable solar panel using the element selenium. However, they were only about 1% efficient and never deployed at scale.

It would not be until 1953, when scientists Calvin Fuller, Gerald Pearson and Daryl Chapin working at Bell Labs cracked the switch from selenium to silicon, that the modern solar panel was created.

Bell Labs unveiled the breakthrough invention to the world the following year, using it to power a small toy Ferris wheel and a radio transmitter.

Fuller, Pearson and Chapin’s solar panel was only 6% efficient, a big step forward for the time, but today panels can convert more than 40% of the sun’s light into electricity.

The wind pioneers who believed in self-generation

Offshore wind farm near Øresund Bridge between Sweden and Denmark

Like hydropower, wind has long been harnessed as a source of power, with the earliest examples of wind-powered grain mills and hydro pumps appearing in Persia as early as 500 BC.

The first electricity-generating windmill was used to power the mansion of Ohio-based inventor Charles Brush. The 60-foot (18.3 metres) wooden tower featured 144 blades and supplied about 12 kW of electricity to the house.

Charles Brush’s wind turbine charged a dozen batteries each with 34 cells.

The turbine was erected in 1888 and powered the house for two decades. Brush wasn’t just a wind power pioneer either, and in the basement of the mansion sat 12 batteries that could be recharged and act as electricity sources.

Small turbines generating between 5 kW and 25 kW were important at the turn of the 19thinto the 20thcentury in the US when they helped bring electricity to remote rural areas. However, over in Denmark, scientist and teacher Poul la Cour had his own, grander vision for wind power.

La Cour’s breakthroughs included using a regulator to maintain a steady stream of power, and discovering that a turbine with fewer blades spinning quickly is more efficient than one with many blades turning slowly.

He was also a strong advocate for what might now be recognised as decentralisation. He believed wind turbines provided an important social purpose in supplying small communities and farms with a cheap, dependable source of electricity, away from corporate influence.

In 2017, Denmark had more than 5.3 gigawatts (GW) of installed wind capacity, accounting for 44% of the country’s power generation.

The prince and the power plant

Larderello, Italy

Italian princes aren’t a regular sight in the history books of renewable energy, but at the turn of the last century, on a Tuscan hillside, Piero Ginori Conti, Prince of Trevignano, set about harnessing natural geysers to generate electricity.

In 1904 he had become head of a boric acid extraction firm founded by his wife’s great-grandfather. His plan for the business included improving the quality of products, increasing production and lowering prices. But to do this he needed a steady stream of cheap electricity.

In 1905 he harnessed the dry steam (which lacks moisture, preventing corrosion of turbine blades) from the geographically active area near Larderello in Southern Tuscany to drive a turbine and power five light bulbs. Encouraged by this, Conti expanded the operation into a prototype power plant capable of powering Larderello’s main industrial plants and residential buildings.

It evolved into the world’s first commercial geothermal power plant in 1913, supplying 250 kW of electricity to villages around the region. By the end of 1943 there was 132 megawatts (MW) of installed capacity in the area, but as the main source of electricity for central Italy’s entire rail network it was bombed heavily in World War Two.

Following reconstruction and expansion the region has grown to reach current capacity of more than 800 MW. Globally, there is now more than 83 GW of installed geothermal capacity.

The engineer who took on an oil crisis with wood 

Compressed wood pellet storage domes at Baton Rouge Transit, Drax Biomass’ port facility on the Mississippi River

While sawmills had experimented with waste products as a power sources and compressed sawdust sold as domestic fuel, it wasn’t until the energy crisis of the 1970s that the term biomass was coined and wood pellets became a serious alternative to fossil fuels.

As a response to the 1973 Yom Kippur War, the Organization of Arab Petroleum Exporting Countries (OPEC) placed oil embargoes against several nations, including the UK and US. The result was a global price increase from $3 in October 1973 to $12 in March 1974, with prices even higher in the US, where the country’s dependence on imported fossil fuels was acutely exposed.

One of the most vulnerable sectors to booms in oil prices was the aviation industry. To tackle the growing scarcity of petroleum-based fuels, Boeing looked to fuel-efficiency engineer Jerry Whitfield. His task was to find an alternative fuel for industries such as manufacturing, which were hit particularly hard by the oil shortage and subsequent recession. This would, in turn, leave more oil for planes.

Wood pellets from Morehouse BioEnergy, a Drax Biomass pellet plant in northern Louisiana, being unloaded at Baton Rouge Transit for storage and onward travel by ship to England.

Whitfield teamed up with Ken Tucker, who – inspired by pelletised animal feed – was experimenting with fuel pellets for industrial furnaces. The pelletisation approach, combined with Whitfield’s knowledge of forced-air furnace technology, opened a market beyond just industrial power sources, and Whitfield eventually left Boeing to focus on domestic heating stoves and pellet production.

One of the lasting effects of the oil crisis was a realisation in many western countries of the need to diversify electricity generation, prompting expansion of renewable sources and experiments with biomass cofiring. Since then biomass pellet technology has built on its legacy as an abundant source of low-carbon, renewable energy, with large-scale pellet production beginning in Sweden in 1992. Production has continued to grow as more countries decarbonise electricity generation and move away from fossil fuels.

Since those original pioneers first harnessed earth’s renewable sources for electricity generation, the cost of doing so has dropped dramatically and efficiency skyrocketed. The challenge now is in implementing the capacity and technology to build a safe, stable and low-carbon electricity system.

What causes power cuts?

16 January 2019

Power generation

On the night of 5 December 2015, 61,000 homes and properties across Lancaster were plunged into darkness. Storm Desmond had unleashed torrents of rain on Great Britain, causing rivers to swell and spill over. With waters rising to unprecedented levels, the River Lune began threatening to flood Lancaster’s main electricity substation, the facility where transformers ‘step down’ electricity’s voltage  from the transmission system so it can be distributed safely around the local area.

To prevent unrepairable damage, the decision was taken to switch the substation off, cutting all power across the region. Lights, phones, internet connections and ATMs all went dead across the city. It would take three days of intensive work before power was restored.

It was a bigger power outage than most, but it offers a unique glimpse into the mechanisms behind a blackout – not only how they’re dealt with, but how they’re caused.

What causes blackouts in Great Britain?  

Flooded electricity sub station in Lancaster, Sunday 6 December 2015

When the lights go out, a common thought is that the country has ‘run out’ of electricity. However, a lack of electricity generation is almost never the cause of outages. Only during the miners’ strikes of 1972 were major power cuts the result of lack of electricity production.

Rather than meeting electricity demand, power cuts in Great Britain are more often the result of disruption to the transmission system, caused by unpredictable weather. If trees or piles of snow bring down one power line, the load of electric current shifts to other lines. If this sudden jump in load is too much for the other lines they automatically trip offline to prevent damage to the equipment. This in turn shifts the load on to other lines which also then trip, potentially causing cascading outages across the network.

Last March’s ‘Beast from the East’, which brought six days of near sub-zero temperatures, deep snow and high winds to Great Britain, is an example of extreme weather cutting electricity to as many as 18,000 people.

High-winds brought trees and branches down onto powerlines, while ice and snow impacted the millions of components that make up the electricity system. Engineering teams had to fight the elements and make the repairs needed to get electricity flowing again.

Lancaster was different, however. With the slow creep of rising rainwater approaching the substation, the threat of long lasting damage was plain to see in advance, and so rather than waiting for it to auto-trip, authorities chose to manually shut it down.

Getting reconnected

An emergency generator brought from London is reversed into position adjacent to the sub station in Bold Street Morecambe, near Lancaster, Monday 7 December 2015

Electricity North West is Lancaster’s network operator and after shutting down the substation, it began the intensive job of trying to restore power. On Monday 7 December, two days after the storm hit, the first step of pumping the flooded substation empty of water had finally been completed and the task of reconnecting it began.

To begin restoring power to the region 75 large mobile generators were brought from as far away as the West Country and Northern Ireland and hooked up to the substation, allowing 22,000 customers to be reconnected.

Once partial power was restored, the next challenge lay in repairing and reconnecting the substation to the transmission network. While shutting the facility had prevented catastrophic damage, some of the crucial pieces had to be completely replaced or rebuilt. After three days of intensive engineering work the remaining 40,000 properties that had lost power were reconnected.

Preventing blackouts in a changing system

The cause and scale of Lancaster’s outage were unusual for Great Britain’s electricity system but it does highlight how quickly a power cut may arise. In a time of transition, when the grid is decarbonising and the network is facing more extreme weather conditions because of climate change, it could create even more, new challenges.

Coal is scheduled to be taken entirely off the system after 2025, making the country more reliant on weather-dependent sources, such as wind and solar – potentially increasing the volatility of the system.

On the other hand, growing decentralised electricity generation may reduce the number of individual buildings affected by outages in the future. Solar generation and storage systems present on domestic and commercial property may also reduce dependency on local transmission systems and the impact of disruptions to it.

The cables and poles that connect the transmission system will always be vulnerable to faults and disruptions. However, by preparing for the future grid Great Britain can reduce the impact of storms on the electricity system.

If you’re experiencing a power cut in your area, please call the toll-free number 105 (in England, Scotland and Wales) to reach your local network operator.

Magnets, metal and motion – electricity generation simplified

2 November 2018

Power generation

Generating electricity in a power station is a huge, complex operation. Thousands of tonnes of fuel, millions of gallons of water, intense temperatures and incredibly high pressures all go into spinning turbines and turning generators, which in turn creates electricity.

But strip it back to its basics and making electricity is relatively simple. All it takes is a magnet, metal and motion.

Turning motion into electricity

British scientist Michael Faraday first realised the relationship between magnetic fields and electricity in 1831. He noticed when a magnet moved through a coil of copper, a current flows through the wires. The same thing happens if the wires are moved and the magnetic is static. All that matters is that there is motion in a magnetic field, allowing the kinetic energy to be converted into electrical energy. This simple observation is still the basis of how electricity is generated around the world today.

To replicate this process in miniature, we can use spinning copper wires and an everyday magnet. At this scale the electric current induced is very small – not even enough to power an LED light. However, an ammeter shows the tiny voltage passing along the wires. This is possible because of the relationship between magnetic fields and electric currents.

How electrons create electricity

The key to how magnetic fields convert motion into electric currents is found in atoms. Every neutral atom’s core is made up of static neutrons and protons, with electrons zooming around them. However, with the right outside force introduced, electrons can be stimulated, which causes them to break away from an atom and set off a chain reaction that knocks other electrons free, in turn creating an electric current.

A magnet can provide this outside force. Passing the magnetic field through copper wires, for example, breaks electrons from their copper atoms and sends them flowing in one direction.

Metals are good at conducting electricity because their atoms have a looser hold on their electrons than materials like wood or glass, making it easier for a magnetic field to free them.

The speed at which the magnetic field passes through the atoms affects how many electrons are broken off from them. If more kinetic energy is put into the magnet and it passes through faster, more electrons are set free and more current flows.

Scaling generation up

It’s this simple principal of magnets, metal and motion that powers most of world, but in power stations it is scaled up and optimised to supply huge amounts of electrical power.

Each of Drax’s 600-plus megawatt generators contains a 120 tonne rotor, which acts as a very strong electromagnet. This sits inside the stator which weighs 300 tonnes, and contains 84, 11-metre long copper bars.

High pressure steam is used to spin a series of turbines, which in turn spin the rotor and its magnetic field at 3,000 rpm. As it spins a voltage is induced in its stator at a frequency of 50 cycles per second (which sets the frequency for the entire grid – 50 Hz), sending electrons zooming through the stator bars which carry a huge electric current.

This is the same in almost every form of electricity generation that uses a rotating generator, from wind to hydro to nuclear to biomass. Solar generation is the exception, but it uses the same principle of knocking around electrons.

Instead of using a magnetic field to break electrons from metal atoms, solar panels use photons from sunlight to free electrons from a negatively charged layer of silicon film. These are then attracted to a layer of positive film which creates an electrical current that is collected and channelled from each solar panel.

At its most-basic, electricity generation is simple and even as the world switches to less carbon-intense means of production, the straightforward concept of using a magnetic, metal and motion will remain at its heart

Does electricity have a smell?

20 July 2018

Electrification

Freshly baked bread, newly cut grass, sizzling bacon. Many of the world’s most evocative smells often need electricity to make them, but does electricity itself have a smell?

The short answer is no. An electric current itself doesn’t have an odour. But in instances when electricity becomes visible or audible it also creates a distinctive smell.

“The smell electricity emits is the contents of the gasses created when electricity conducts through air,” says Drax Lead Engineer Gary Preece. “In an instance of a failure on a switch board, for example, and there’s a flash of electricity, gasses are created from the charged air including ozone.”

It’s the same ozone gas that makes up the lower layer of the earth’s atmosphere and is often described as having a clean, chlorine-like, but burnt, smell. While it can sometimes be dangerous, ozone is also a very useful gas.

What is ozone?

Ozone’s scientific name is trioxide as it is made up of three oxygen molecules. While the normal oxygen we breathe is O2, ozone is O3 and is created by electricity in a similar way to how it forms naturally in the atmosphere.

There are large amounts of oxygen and nitrogen floating around in the atmosphere protecting life on earth from the sun’s intense UV radiation. These rays are so powerful they can ionise the oxygen, ripping it apart into two individual molecules. However, these lonely molecules are highly reactive and will sometimes collide and bond with nearby O2 to create ozone.

An electric current at a high voltage – given the right conditions – will conduct through the air, ionising oxygen in its wake and creating ozone, just as the sun’s UV rays do. When electricity behaves like this it’s known as a corona discharge, which makes a crackling sound and creates a visible plasma.

The most common time people may come into contact with a whiff of ozone is when a storm is approaching. Lighting is essentially a massive plasma that creates ozone as it conducts through the air, with the smell often arriving before the storm hits. It highlights quite how pungent ozone is considering humans can smell it in concentrations as low as 10 parts per billion in ordinary air. 

The concerns and capabilities of ozone

While ozone protects the planet when it’s in the atmosphere, it can be dangerous at ground level where it can also form through naturally occurring gases reacting with air pollution sources. High exposure to ozone at ground level can lead to lung, throat and breathing problems. However, because it also has a damaging effect on bacteria, ozone can be very useful in the medical field, and electricity is being used to deliberately create it.

In fact, ozone has been experimented with in medicine for more than a century, with its ability to attack and kill bacteria making it useful as a disinfectant. During the First World War it was used to treat wounds and prevent them becoming inflamed and was also found to aid blood flow.

Electricity plays an important role in almost everything we interact with on a daily basis, affecting all our senses, even smell.