Tag: technology

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.

How to get more EVs on the roads

25 January 2019

Electrification

From school runs to goods deliveries, getting from A to B is crucial to life in modern Britain. However, a progress report by the Committee on Climate Change (CCC) found that in 2017 transport was the largest greenhouse gas (GHG)-emitting sector in the UK, accounting for 28% of total emissions. Within domestic transport, cars, vans and HGVs are the three most significant sources of emissions, accounting for 87% of the sector’s emissions.

A zero carbon future relies on a major shift away from petrol and diesel engines to electric transport. A recent report, Energy Revolution: A Global Outlook, by academics from Imperial College London and E4tech, commissioned by Drax, examines the decarbonisation efforts of 25 major countries. The report found the UK ranked sixth in sales of new electric vehicles (EVs) in the 12 months to September 2018 and seventh for the number of charging points available.

The government’s Road to Zero strategy outlines the country’s target for as many as 70% of new car sales to be ultra-low emission by 2030, alongside up to 40% of new vans. It has, however, been criticised by the Committee on Climate Change as not being ambitious enough. A committee of MPs has suggested 2032 becomes the official target date for banning new petrol and diesel cars, rather than 2040 called for in the strategy.

Even as the range of EVs on the market grows, getting more low-emission vehicles on roads will require incentives and infrastructure improvements. Here’s how some of the countries leading the shift to electrified transport are driving adoption.

Expanding charging infrastructure

One of major barriers to EV adoption is a lack of public charging facilitates, coupled with reliability issues across a network that includes both old hardware and a plethora of apps and different connections. No one wants to set off on a long journey unsure of whether they’ll be able to find a recharging point before their battery goes flat.

According to the Energy Revolution report, there is one charger for every 5,000 people in the UK, compared to one for every 500 people in Norway, the leading country for charging points. The Scandinavian country’s government has invested heavily in its policy of placing two fast charging stations for every 50 km of main road, covering 100% of the cost of installation.

Government support has also been crucial in second and third ranked countries, The Netherlands and Sweden, respectively. The Dutch Living Lab Smart Charging is a collaboration between government and private organisations to use wind and solar to change vehicles. While Sweden has combined its ‘Klimatklivet’ investment scheme for both public and private charge points, with experiments, such as charging roads.

China, where half of the world’s 300,000 charge points are located, has issued a directive calling for the construction of 4.8 million electric charging points around the country by 2020. It’s also assisting private investments to make charging stations more financially viable.

The UK’s Road to Zero Strategy is to expand charging infrastructure through a £400 million joint investment fund with private investors.

Drax’s Energising Britain report found the UK is on track to meet its 2030 target of 28,000 installed chargers ahead of time. However, deployment still clusters around London, the South East and Scotland.

More direct government incentives or policies may be needed to balance this disparity and in the UK, the Scottish Government is leading the pack with a 2032 ban on new petrol and diesel cars plus a range of initiatives including public charging networks and the Switched on Towns and City Fund.

Charging points are necessary for electrified roads. However, it’s a chicken-and-egg situation –more chargers don’t mean more EVs. Getting more EVs on roads also requires financial incentive.

Money makes the wheels go around  

Putting infrastructure in place is one thing, but the reality is EVs are expensive, especially new ones and cold hard cash is an important driver of adoption.

Financial incentives have been a part of Norway’s policies since the 1980s, with the country’s high fuel prices, compared to the US for example, further helping to make EVs attractive. Current benefits for EV owners include: no import or purchase taxes, no VAT, no road tax, no road tolls, half price on ferries and free municipal parking. There are also non-financial incentives such as bus-lane usage.

Sweden, the second ranked country for new EV sales in 2018, is a similar case where high fuel prices are combined with a carrot-and-stick approach of subsidies for EVs and rising road taxes for fossil fuel-powered vehicles, including hybrids.

The UK has had a grant scheme in place since 2011, but last year removed hybrid vehicles from eligibility and dropped the maximum grant for new EV buyers from £4,500 to £3,500. EVs are also exempt from road taxes. In April 2019, Transport for London is implementing a Low Emissions Zone (ULEZ) which exempts EVs from a daily charge.

Subsidies for both buyers and vehicle manufacturers have been a cornerstone of China’s policies, with support coming up to around $15,000 per vehicle. Chinese EV buyers can also skip the lottery system for new license plates the country has in place to reduce congestion.

Heavy subsidies have allowed the country to claim as much as 50% of the entire EV passenger market, however, it makes change expensive and the government is now preparing to find a more sustainable way of driving adoption.

Preparing for transport beyond subsidies

China isn’t afraid to strong-arm manufacturers into building more EVs. Companies with annual sales of more than 30,000 vehicles are required to meet a quota of at least 10% EVs or hybrids. However, the government has begun to scale back subsidies in the hope it will drive innovation in areas such as batteries, robotics and automation, which will in turn reduce the price for end consumers.

Norway, which owes so much of its decarbonisation leadership in low-carbon transport to subsidies, is also grappling with how to move away from this model. As EVs creep increasingly towards the norm, the taxes lost through EV’s exclusions become more economically noticeable. While the government says the subsidies will remain in place until at least 2020, different political parties are calling to make the market commercially viable.

There is also concern the schemes only pass on savings to those who can afford new EV models, rather than the wider population, who face higher taxes for being unable to upgrade.

It’s not just governments’ responsibility to make new markets for EVs sustainable, but for business to innovate within the area too. Drax Group CEO Will Gardiner recently said his company must help to “ensure no-one is left behind through the energy revolution”.

That’s a view welcomed by politicians from all sides of the political spectrum concerned not just about mitigating man-made climate change but also to ensure a ‘just transition’ during the economy’s decarbonisation.

Energy and Clean Growth Minister Claire Perry spoke at an Aldersgate Group event in London in January:

“It’s been very easy, in the past, for concerns about the climate to be dismissed as the worries of the few, not the many. Luckily, we’ve been able to strip out a lot of the myths surrounding decarbonisation and costs –but we have to be mindful that this is a problem which will have to be solved by the many, not just the middle class.”

Many countries have set ambitious targets for when the ban of new petrol and diesel vehicles will come into effect. Government involvement and subsidies will be crucial but may prove economically challenging in the longer term.

Explore the full reports:

Energy Revolution: A Global Outlook

I. Staffell, M. Jansen, A. Chase, E. Cotton and C. Lewis (2018). Energy Revolution: Global Outlook. Drax: Selby.

Energising Britain: Progress, impacts and outlook for transforming Britain’s energy system

I. Staffell, M. Jansen, A. Chase, C. Lewis and E. Cotton, (2018). Energising Britain: Progress, impacts and outlook for transforming Britain’s energy system. Drax Group: Selby.

 

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

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?  

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

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.

What can be made from captured carbon?

11 September 2018

Carbon capture

The combination of a heatwave and an entertaining world cup campaign put big demands on Great Britain’s beer supplies this summer. But European-wide carbon dioxide (CO2) shortages put a hold on that celebratory atmosphere as word spread that a lack of bubbles could result in the country running out of beer.

The drinks business managed to hold out, but the threat of long term CO2 shortages still lingers over the continent. One possible – and surprising – solution could lie in electricity generation, thanks to the capturing and storing of its carbon emissions.

Carbon capture and storage (CCS) is one of the key technologies in need of development to allow nations to meet their Paris Agreement goals. It has the potential to stop massive amounts of emissions entering the atmosphere, but it also raises the question: what happens to all that carbon once it’s captured?

Drax recently met with the British Beer & Pub Association to discuss using some of the carbon it plans to capture in its upcoming trial of Bioenergy Carbon Capture and Storage (BECCS) to keep the fizz in drinks.

It’s a novel solution to a potential problem, but it’s just one of the many emerging possibilities being developed around the world.

Smarter sneakers

Carbon capture is all about reducing carbon footprints – a phrase energy company NRG interpreted quite literally by creating ‘The Shoe Without A Footprint’. The white trainer was created to showcase the abilities of carbon capture, use and storage (CCuS) and is made of 75% material produced from captured emissions that have been turned into polymers, a molecular structure similar to plastics.

Only five pairs of the sneakers were created as part of NRG’s Carbon XPrize competition to find uses for captured carbon. However, they remain symbolic of the versatility offered by captured and stored carbon and its potential to contribute to the manufacture of everyday objects.

Better furniture

Finding an alternative to plastics is one of the key ways of facilitating a move away from global dependencies on crude oil. Sustainable materials company Newlight uses captured CO2 or methane emissions to create a bioplastic called AirCarbon –  a thermopolymer, which means it can be melted down and reshaped.

The company has teamed up with IKEA, which will buy 50% of the 23,000 tonnes of bioplastic Newlight’s plant produces per year. It’s part of the Swedish furniture giant’s efforts to increase the amount of recycled materials it uses and means upcycled carbon could soon be appearing in millions of homes around the world.

Cleaner concrete

If the shoes people walk around on can be made from captured carbon, so too can the cities they walk within. Making concrete is a notoriously dirty process. Cement, the main binding agent in concrete, is thought to contribute to as much as 5% of the world’s greenhouse gas emissions, but this could change thanks to clever use and implementation of carbon capture technology.

At one level, CCS can be introduced to capture emissions from the manufacturing process. On another, the CO2 captured can be used as a raw material from which to create the concrete, effectively ‘locking in’ carbon and storing it for the long term.

Teams of engineers, material scientists and economists at UCLA who have worked on the problem for 30 years have succeeded in creating construction materials from CO2 emissions in lab conditions using 3D printing technology. Now it’s just a matter of scaling it up to industrial usage.

A metal alternative

Carbon nanotubes are stronger than steel but lighter than aluminium, which makes them a hugely useful material. They’re currently used in jets, sports cars and even in industrial structures, but producing them can be expensive and, until recently, could not utilise CO2 for manufacture. A team from George Washington University is changing that.

Its C2CNT technology splits captured CO2 into oxygen and carbon in a molten carbonate bath using electrolysis. From here the carbon is repurposed into carbon nanotubes at a high rate and lower cost than previous methods.

Future fuels

Transportation is one of the major emitters of carbon around the world, so any way it can be reduced or re-used in this field will be a huge positive. Carbon recycling company LanzaTech has developed a way to do this via a process that uses anaerobic bacteria to ferment emissions into cleaner chemicals and fuels.

Its first facility, opening this year in China, will create fuel-grade bioethanol that can be blended with gasoline to create vehicle fuel, or even converted into jet fuel with 65% lower greenhouse gas emissions.

Aviation, too, can benefit from carbon recycling through the creation of synthetic crude oil and gas using CO2. Technology company Sunfire is developing processes that combine hydrogen (set to become a major part of industry and transport) and biogenic CO2, (emissions from natural sources), to create synthetic hydrocarbons that could fuel planes.

From Silicon Valley to Valles Marineris

Earth isn’t the only place humans are innovating around carbon capture – at least, right now. With the race to send men and women to Mars stepping up, the challenges of dealing with its inhospitable atmosphere (which is 95% CO2) and ensuring a minimal human impact to the planet are becoming more acute. Carbon capture and use presents an opportunity to tackle both.

Californian company Opus 12 has developed a device that recycles CO2 from ambient air and industrial emissions and turns it into fuels and chemicals using only electricity and water. The device has the CO2 conversion power of 37,000 trees (or 64 football fields of dense forest) packed into the volume of a suitcase, and can convert CO2 into 16 different products.

In the long-term, the technology might provide critical services for human colonies on the Red Planet by capturing and using CO2 from the atmosphere or any future Mars-based factories. The Opus 12 device can also use ice (buried on the planet in places that could be accessible to astronauts) to convert Mars CO2 into plastic to make bricks and tools, methane that can form rocket fuel, and feedstocks for microbes to create medicine or food.

Turning pollution into possibilities

Many of these technologies are in their infancy, but the possibilities they present are very real. In fact, Drax’s upcoming trial of BECCS will see it capture and store as much as a tonne of carbon every day.

The proliferation of this technology in industry and electricity production – and the resultant increase in captured carbon – will help encourage more companies to see CO2 emissions as an opportunity for revenue while helping countries meet their Paris Agreement emissions goals.

Learn more about carbon capture, usage and storage in our series:

How turbines came to power the world

5 September 2018

Power generation

Charles Algernon Parsons knew he was onto something in 1884. The young engineer had joined a ship engineering firm and developed a steam turbine engine, which he immediately saw had a bigger potential than powering boats.

He connected it to a dynamo, turning it into a generator capable of producing up to 7.5 kilowatts (kW) of power, and in the process kickstarted an electrical and mechanical revolution that would reshape how electricity was produced and how the world worked.

Today turbine-based generation is the dominant method for electricity production throughout the world and even now – almost a century and a half later – Parsons’ turbine concept remains largely unchanged, even if the world around it has.

Steam dreams

Throughout the 20th and into the current century, electricity generation has depended on steam power. Be it in a coal, nuclear or biomass power plant, heating water into highly pressurised steam is at the core of production.

Greek mathematician and inventor Hero of Alexandria is cited as building the first ever steam engine of sorts with his aeolipile, which used steam to spin a hollow metal sphere. But it wasn’t until the 18th century, when English ironmonger Thomas Newcomen designed an – albeit inefficient – engine to pump water out of flooded mines, that steam became a credible power in industry.

Scottish engineer James Watt, from whose name the unit of energy comes from, built on these humble beginnings and turned steam into the power behind the industrial revolution around 1764 when he added an condensing chamber to Newcomen’s original design.

It was the combination of this engine with Thomas Edison’s electrical generator late in the 19th century that first made large-scale electricity production from steam a reality.

The turbine takes over

Steam engines and steam power was not a new concept when Parson began his explorations in the space. In fact, nor were steam turbines. Others had explored ways to use stream’s velocity to spin blades rather than using its pressure to pump pistons, in turn allowing rotors to spin at much greater speeds while requiring less raw fuel.

What made Parsons’ design so important was its ability to keep rotational speeds moderate while also extracting as much kinetic energy from steam jets as possible.

He explained in a 1911 Rede Lecture that this was done by “splitting up the fall in pressure of the steam into small fractional expansions over a large number of turbines in series,” which ensured there was no one place the velocity of the blades was too great.

The design’s strength was also apparent at scale. In 1900 his company (which was eventually acquired by Siemens) was building turbine-generator units capable of producing 1,000 kW of electricity. By 1912, however, the company was installing a 25,000 kW unit for the City of Chicago. Parsons would live to see units reach 50,000 kW and become the primary source of electricity generation around the world.

Turbines in the modern grid

The world is a vastly different place to the one in which Parson designed his turbine, yet the fundamentals of his concept have changed very little. The results of what they achieve and the scales at which they work, however, have increased significantly.

Today the turbines that make up Drax’s six generating units are each capable of producing more than 600 MW (or 6,000,000 kW) of electricity with the shape, materials and arrangement of blades carefully designed to maximise efficiency.

And while that first design was purely with steam in mind, turbine technology has advanced beyond dependency on a single power source, and has been developed to accommodate for the shift towards lower-carbon power sources.

One such example is gas turbines, which work by sucking in air through a compressor, which is then heated by burning natural gas, in turn spinning a turbine as it expands. These can jump into action much faster than other turbines as they don’t require any steam to be created to power them.

Renewable sources, such as hydro and wind power, also depend on spinning turbines to generate electricity. Where these differ from gas or steam-powered turbines is that rather than being encased in metal and blasted with gases, wind and hydro turbines’ blades are exposed, so flowing air or water can spin them, powering a generator in turn.

Turbine technology helped bring access to electricity around the world, but the ingenuity and flexibility of the design means it is now serving to adapt electricity production for the post-coal age.

How to switch a power station off coal

22 August 2018

Sustainable bioenergy
Turbine hall at Drax Power Station

In 2003, the UK’s biggest coal power station took its first steps away from the fossil fuel which defined electricity generation for more than a century. It was in that year that Drax Power Station began co-firing biomass as a renewable alternative to coal.

It symbolised the beginnings of the power station’s ambitious transformation from fossil-fuel stalwart to the country’s largest single-site renewable electricity generator. This plan presented a massive engineering challenge for Drax, with significant amounts of new knowledge quickly needed.

Fifteen years later, three of its generating units now run entirely on compressed wood pellets, a form of biomass, while coal has been relegated to stepping in only to cover spikes in demand and improve system stability.

Now Drax has converted a fourth unit from coal to biomass. This development represents the passing of a two thirds marker for the power station’s coal-free ambitions and adds 600-plus megawatts (MW) of renewable electricity to Great Britain’s national transmission system.

Building on the past

Drax first converted a coal unit to biomass in 2013, with two more following in 2014 and 2016. This put Drax in an interesting position going into a new conversion: on one hand, it is one of the most experienced generators in the world when it comes to dealing with and upgrading to biomass. On the other, it’s still relatively new to the low carbon fuel compared with its dealings with coal.

Adam Nicholson

“We’ve decades of understanding of how to use coal, but we’ve only been operating with biomass since we started the full conversion trials in 2011,” says Adam Nicholson, Section Head for Process Performance at Drax Power. “We’ve got few running hours under our belts with the new fuel versus the hundreds of man years of coal knowledge and operation all around the country.”

When converting a generating unit, the steam turbine and generator itself remain the same. The difference is all in the material being delivered, stored, crushed and blown into the boiler and burned to heat up water and create steam. And because biomass can be a volatile substance – much more so than coal – this process must be a careful one.

Drax could build on the learnings and equipment it had already developed for biomass such as specially built trains and pulverising mills, but storage proved a bigger issue. The giant biomass domes at Drax that make up the EcoStore are advanced technological structures carefully attuned to storing biomass, but for Unit 4, they were off limits.

Instead Drax engineers had to come up with another solution.

The journey of a pellet through the power station

Normally wood pellets are brought into Drax by train, unloaded and stored in the biomass domes before travelling through the power station to the mills and then boilers. Unit 4, however, sits in the second half of the station – built 12 years after the first. This slight change in location presented a problem.

“There’s no link from the eco store to Unit 4 at all,” explains Nicholson. “You can’t use the storage domes and that whole infrastructure to get anything to Unit 4.”

Drax engineers set about designing a new conveyor system that could connect the domes to the mills and boiler that powers Unit 4. After weeks of design, the team had a theoretical plan to connect the two locations with one problem: it was entirely uneconomical.

Rail unloading building 1 and storage silos

“If we were building a new plant it would be relatively easy, because you could plan properly and wouldn’t have existing equipment in the way,” says Nicholson.

“We had to plan around it and make use of the pre-existing plant.”

Within that pre-existing plant though were vital pieces of equipment, some of which had laid dormant since Drax stopped fuelling its boilers with a mixture of coal and biomass and opted instead for full unit conversions.

Drax began cofiring across all six units in 2003, using two different materials – a mix of around 5% biomass and 95% coal. A direct injection facility was added in 2005. It involved blowing crushed wood pellets into coal fuel lines from two of the power station’s 60 mills.

Then, the amount of renewable power Drax was able to generate roughly doubled in the summer of 2010 when a 400 MW co-firing facility became operational.

Back to the present day, it’s fortunate for the Unit 4 conversion that the co-firing facility includes its own rail unloading building (RUB 1) and storage silos. They are located much closer to the unit than the bigger RUB 2 and the massive biomass domes.

This solved the problem of storage but moving the required volumes of biomass through the plant without significant transport construction still posed a challenge.

Rail unloading building 1 and storage silos for Unit 4 [left], EcoStore biomass domes for units 1-3 [right]

To tackle this the team modified a pneumatic transport system, previously tested during co-firing, to have the capability to blow entire pellets from the storage facilities around the power station at speeds of more than 20 metres per second. The success of this system proved key – it was the final piece necessary to make the conversion of Unit 4 economical.

The post-coal future

Andy Koss

For now, Drax’s fifth and sixth generating unit remain coal-powered, but are called upon less frequently. With Great Britain set to go completely coal-free by 2025, there are plans to convert these too, but as part of a system of combined cycle gas turbines and giant batteries rather than biomass powered units.

It’s an opportunity for Drax to again leverage its pre-existing plant and provide the grid with a fast acting-source of lower-carbon electricity. As with converting to biomass, it will pose a complex new engineering challenge – one that will prepare Drax to meet the future needs of grid as it continues to change and demand greater flexibility from generators.

“The speed at which the Unit 4 project has been delivered is testament to the engineering expertise, skill and ingenuity we continue to see at Drax. We’re nimble and innovative enough to meet future challenges,” says Andy Koss, Chief Executive, Drax Power.

“We may look very different in 10 or 20 years’ time, but the ethos of that innovation and agility is something that will persist.”

Repowering the remaining coal plant with gas and up to 200 MW of batteries will sit alongside research into areas such as carbon capture, use and storage (CCuS) that is all geared towards expanding Drax Power beyond a single site generator into a portfolio of flexible power production facilities.

Unit 4’s conversion is more than just a step beyond halfway for the power station’s decarbonisation, but a significant step towards becoming entirely coal-free.

Find out more about Unit 4.

How the heatwave affects electricity demand

Iain Staffell, Imperial College London

27 July 2018

Opinion

16.5 degrees is the Goldilocks temperature for the Brits – not hot enough for air-con, not too cold to put the heating on. In March we saw how the Beast from the East caused a surge in demand, now the long summer heatwave is doing the same.

June 23rd marked the start of the heatwave, with daytime temperatures surpassing 30°C in Scotland and Wales. The last week of June was 3.3°C warmer than the previous week, and demand was 860 MW higher (see chart below). This rise is equivalent to power demand from an extra 2.5 million households.

This reflects the growing role of air conditioning and refrigeration in shops, and cooling for data centres. Global electricity demand from cooling is rising dramatically, and is seen as a ‘blind spot’ in the global energy system.  This will become more important as global temperatures, and more importantly, global incomes rise. However, it is easier to deal with than cold spells during winter because demand is low and solar PV output is high.

Below 14°C, demand increases by 750 MW for every degree it gets colder as buildings need more heating. Around a tenth of British homes have electric heating, as do half of commercial and public buildings. And while the UK is not synonymous with air conditioners, demand rises by 350 MW for each degree that temperature rises above 20°C.

This effect may well grow stronger in the coming years. National Grid expect that the peak load from air conditioners will triple in the coming decade. Perhaps events such as the current prolonged heatwave may spur more households to invest in air conditioning.

Read the press release

Explore power grid data during the heatwave beginning 23rd June

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.