Tag: technology

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.

Keeping the electricity system’s voltage stable

15 May 2018

Power generation
Electricity high voltage sign

In day-to-day life, the electricity system normally plays a consistent, unfluctuating role, powering the same things, in the same way. However, behind the scenes electricity generation is a constant balancing act to keep the grid stable.

Power stations themselves are like living animals, in need of continuous adjustment. Transmission networks need continual maintenance and keeping the whole grid at a frequency of 50 Hz takes careful monitoring and fine-tuning.

One of the other constant challenges for Great Britain’s electricity system is keeping voltage under control.

Keeping the volts in check

Voltage is a way of expressing the potential difference in charge between two points in an electrical field. In more simplistic terms, it acts as the pressure that pushes charged electrons (known as the current) through an electric circuit. 

Great Britain’s National Grid system runs at a voltage of 400 kilovolts (kV) and 275kV (Scotland also uses 132kV). It is then reduced in a series of steps by transformers to levels suitable for supply to customers, for example 11kV for heavy industrial or 230 volts (V) when delivered to homes by regional distribution networks.

UK electricity voltage system

Keeping the voltage steady requires careful management. A deviation as small as 5% above or below can lead to increased wear and tear of equipment – and additional maintenance costs. Or even large-scale blackouts. Power stations such as Drax can control the voltage level through what’s known as reactive power.

“If voltage is high, absorbing reactive power back into the generator reduces it,” says Drax Lead Engineer Gary Preece. “By contrast, generating reactive power increases the voltage.”

Reactive power is made in an electricity generator alongside ‘active power’ (the electricity that powers our lights and devices) and National Grid can request generators such as Drax to either absorb or produce more of it as it’s needed to control voltage.

So how is a generator spinning at 3,000 rpm switched from producing to absorbing reactive power? All it takes is the turn of a tap.

Absorbing reactive power

Taps along a transformer allow a certain portion of the winding – which make up a transformer’s active part with the core – to be selected or unselected. This allows the transformer to alter what’s known as the ‘phase angle’, which refers to the relationship between apparent power (made up of reactive power and active power) and active power. This change in the phase angle regulates the ‘power factor’.

Power factor is measured between 0 and 1. Between 1 and 0 lagging means a generator is producing reactive power and increasing overall voltage, whereas between 1 and 0 leading means it is absorbing reactive power and reducing voltage.

That absorbed reactive power doesn’t just disappear, rather it transfers to heat at the back end of the power station’s generator. “Temperatures can be in excess of 60 degree Celsius,” says Preece. “There’s also a lot of vibration caused by the changes in flux at the end of the generator, this can cause long term damage to the winding.”

As the generators continue to produce active power while absorbing reactive power the conditions begin to reduce efficiency and, if prolonged, begin to damage the machines. Drax’s advantage here is that it operates six turbines, all of which are capable of switching between delivering or absorbing reactive power, or vice versa, in under two minutes.

UK electricity grid

Voltage management in a changing grid

The changing nature of Great Britain’s energy supply means voltage management is trickier than ever. Voltage creeps up when power lines are lightly loaded. The increase of decentralised generation – such as solar panels and small-scale onshore wind farms operating to directly supply specific localities or a number of customers embedded on regional electricity networks –  means this is becoming more common around the grid. This creates a greater demand for the kind of reactive power absorption and voltage management that Drax Power Station carries out.

Grid-scale batteries are being increasingly developed as a means of storing power from weather dependent renewable sources. This power can then be pumped onto the grid when demand is high. In a similar manner, these storage systems can also absorb reactive power when there’s too much on the system and discharge it when it’s needed – bringing the voltage down and up respectively.

Electricity storage

“The trouble is, grid-scale battery storage systems need to be absolutely huge, and a 100 MW facility would be close to the size of football field and double stacked,” explains Preece. “They are also not synchronised to the grid as a thermal turbine generator would be.” Subsequently there is no contribution to inertia.

As Great Britain’s power system continues to evolve, maintaining its stability also needs to adapt. Where once the challenge lay in keeping voltage high and enough reactive power on the grid, today it’s absorbing reactive power and keeping voltage down. It highlights the need for thermal generators that are designed to quickly switch between generating and absorbing to support the wider network.

This story is part of a series on the lesser-known electricity markets within the areas of balancing services, system support services and ancillary services. Read more about reserve power, system inertia, black start, reactive power and frequency response. View a summary at The great balancing act: what it takes to keep the power grid stable and find out what lies ahead by reading Balancing for the renewable future and Maintaining electricity grid stability during rapid decarbonisation.

Can we see electricity?

4 May 2018

Electrification

A 14th century carrack quietly sails through the currents of the Atlantic Ocean in the middle of the night. Its navigation relies on the stars shining above, its power on the wind blowing behind. It’s a far cry from the technologically advanced vessels sailing today’s seas.

It was here, long before civilisation began using and generating electricity, that the ghostly, blue-white glow of electricity acting upon air molecules was often seen as it hovered around ships’ masts.

This phenomenon is known as St. Elmo’s Fire, after Saint Erasmus of Formia – the patron saint of sailors – and occurs following thunderstorms when the electric field still present around an object (such as a lightning rod or a ship’s mast) causes air molecules to break up and become charged, creating what’s known as a plasma.

St. Elmo’s fire on a cockpit window

For sailors in an era long before satellite guidance it was a good omen. What they didn’t realise, however, was it was one of the rare instances when electricity acts in a way that changes it from an unseen force to something we can see, hear and even smell.

The science behind seeing electricity

Normally, we can’t see electricity. It’s like gravity – an invisible force we only recognise when it acts upon other objects. In the instance of electricity, the most common way it affects objects is by charging electrons, and because these are so small, so plentiful and move so quickly once charged, they are all but invisible to the naked human eye.

However, there are instances when conditions enable an electric current to conduct through the air, which can create sound and generate a visible plasma.

“You can see electricity in certain instances because it’s ionising the air,” says Drax Lead Engineer Gary Preece. In the process of ionising, the molecules that make up air become electrically charged, which can create a plasma.

“The electric current is able to bridge the air gap through the ionised air and to earth,” explains Preece. “You need to have that path to earth for it to create a spark.”

It’s a similar process to how a spark plug works or how lightning becomes visible. While there is still scientific debate around how clouds become electrically charged, the flashes seen on the ground are caused by discharges between clouds, or from clouds to the earth, creating a very hot and bright plasma.

The atmospheric conditions of our earth being largely oxygen and nitrogen give lightning a whitish-blue colour, like St. Elmo’s Fire. Altering these conditions so electricity passes through a gas such as neon changes the colour to a red-orangey shade, which is the principle on which neon lights and signs are built. To achieve different colours, different gases such as mercury and helium are used to fill the tube.

Long before we learned how to manipulate electricity to create different coloured signs we were battling with how to create visible, useful electricity. And it began with the use of arcs.

The architecture of electric arcs

Electric arcs occur when an electric current bridges an air gap. While air is an insulator, electricity’s constant attempts to conduct to earth sometimes enable it to find paths through it, ionising the air molecules and creating a visible plasma bridge along the way. The higher the voltage, the greater the distance it can arc between electrodes.

This property of electricity presents dangers such as arc ‘flashes’, which can occur during electrical faults or short circuit conditions and expel huge amounts of energy, sometimes creating temperatures as high as 35,000 degrees Fahrenheit – hotter than the sun’s surface.

When controlled, electrical arcs can be very useful. These bright glowing bridges were used in the first practical electric lights after Humphry Davy began showcasing the technology in the early 19th century.

But the need to replace carbon electrodes frequently, their buzzing sound and the resultant carbon monoxide emissions meant the technology was soon replaced with the incandescent bulb.

Today arcing is used in welding and in more sophisticated plasma cutting, which focuses a concentrated jet of hot plasma and can make highly precise cuts, while arc furnaces are used in industrial conditions such as steel making.

In fact, some thought has even gone into how we could use an incredibly powerful beam of plasma to create a working lightsabre. And although compelling, the theory of creating this super advanced Star Wars technology is far from being a practical possibility.

In the 14th century seeing electricity was a rare and positive omen. Today, seeing electricity has become far more common, yet when it does happen – through plasma spheres, neon lighting or naturally occurring lightning – the effect is the same: human wonder at seeing an awe-inspiring and seldom-seen force.

Why does electricity have a sound?

11 April 2018

Electrification

On cold, misty mornings, the powerlines, pylons and transformers that make up Great Britain’s electricity system sometimes sound a little different. Stand in a field under a powerline and, in the right conditions, the usual sounds of the countryside might be interrupted by the crackling of electricity.

This buzzing crackle, which can be referred to as a corona discharge, occurs when there’s a change from the normal conditions of a power line’s insulators enabling the electric current to partially conduct along it or through the surrounding air to earth. This can come as a result of weather conditions or deterioration of the insulators.

It’s just one of the instances where electricity changes from an unseen force powering our lights and devices to something we can hear, see and even smell.

Why can we hear electricity?

The source of electricity’s sound is also determined by one of its inherent properties: frequency. Frequency is the measurement of multiple occurrences from events, such as sound waves from vibrations, over a period of time. Any equipment that has a frequency causing mechanical parts to undergo repeated change can be audible.

For example, if we hit a cymbal with a drumstick we can hear a crash because of the frequency of the vibrations the mechanical part (in this case the cymbal) makes. We hear a guitar because its strings are plucked and pulled to create vibration at different frequencies. And we can hear an audible hum in a transformer because electric currents affect its internal structure and cause vibrations.

The buzzy tone this creates can be referred to as ‘mains hum’ and is ever present, although not always perceptible to the human ear. It becomes audible, however, when electricity (specifically alternating current – AC) is applied to a transformer.

Transformers are made of lengths of copper or aluminium, which are wound around a steel laminated core. When AC is applied it magnetises the core and causes steel laminations in the transformer to expand and contract in a process known as magnetostriction. Although only small physical changes, these movements are enough to cause vibration, which in turn creates an audible hum.

The crackling overhead

With more than 7,200 km of overhead powerlines humming away constantly around the country, corona discharges are inevitable and common.

This happens when part of the insulators on a high-voltage line begins to deteriorate, is exposed to weather conditions, is damaged or contaminated, allowing electricity to partially flow along it. The surrounding air becomes electrically charged through a process known as ionisation and causes molecules to become charged and collide.

It’s these collisions in the air that make the corona audible. It can also be visible and gives off a distinct smell of ozone, the gas produced when air is ionised.

Although not dangerous to someone on the ground below, if the insulator on the powerline is left to deteriorate further it can fail completely, leading to earth faults that trip power systems.

Making use of electric hums

The sounds electricity creates may seem like a nuisance but they can also have important uses. One of the most innovative applications is in forensic analysis.

A technique called Electric Network Frequency (ENF) enables forensic scientists to validate audio recording by observing the frequency of the mains hum picked up by audio recordings, which is not audible to humans.

By comparing the frequency of the hum in a recording to a database of the country’s frequencies at given times, it’s possible to verify when and in which country the recording took place and detect any editing.

It highlights not only an innovative use of electricity, but just how pervasive and consistent a presence it is. So, while the ebb and flow of electricity through our lives often goes on without thought, it is always there, humming away while it powers modern life in Great Britain.

 

Bitcoin’s electricity consumption problem

2 March 2018

Electrification

Bitcoin is having a breakout year. Its price fluctuations are making headlines all over the world and major investment banks are finally beginning to take it seriously. In short, bitcoin is no longer a fringe currency – it’s becoming a major player.

But for all the advantages it and other decentralised currencies offer, such as low-transaction fees and no intermediaries, there’s a fundamental problem at their core: they use an extraordinary amount of electricity.

According to bitcoin analysis site Digiconomist, the bitcoin network now uses more than 52 terawatt hours (TWh) every year – more than the whole of Portugal, Ireland or Peru. If this rate of growth continues, it’s forecast that by July 2019 it is expected to use more electricity than the US.

So, while bitcoin may be heralded as a saviour from the monopolies of big banks, what does its incredible appetite for electricity spell for the world’s power networks?

Why does bitcoin use so much electricity?

Bitcoin might be an entirely digital currency, but it still needs to be ‘created’, and this requires a process called bitcoin mining.

Bitcoin is a decentralised network, meaning transactions are carried out directly between parties without any central authority. Instead, bitcoin securely records all its transactions through a network made up of thousands of users’ computers.

Bitcoin mining is essentially the process of recording and adding these transactions to the public network or ledger – known as the blockchain. Every 10 minutes, each pending bitcoin transaction is converted into a complex mathematical problem that needs to be solved.

This is where the ‘mining’ computers come in, which use high-powered processing hardware to tackle the mathematical equations and ‘solve’ each transaction. The first miner to successfully crack one of these problems adds that bitcoin transaction to the ledger and is rewarded with an amount of newly ‘mined’ bitcoins – currently set at 12.5 bitcoins (BTC), worth roughly $140,000.

This process isn’t a quick one and relies on large numbers of high-powered computers to solve the problems. One of the largest bitcoin mining rigs in the world – in Ordos, Inner Mongolia –  is made up of eight buildings crammed with 25,000 machines, all cranking through calculations 24 hours a day.

Unsurprisingly, this huge amount of processing power uses a lot of electricity. It also requires a huge amount of space and generates a lot of heat, all of which have sent bitcoin miners around the world in search of cheap electricity, plentiful space and cold weather.

The search for cheap tech power

Iceland and Sweden have become popular destinations for bitcoin mining thanks to its climate (which keeps computer equipment from overheating) and plentiful electricity. In fact, in Iceland, mining is set to reach 840 gigawatt hours (GWh) this year – more than the 700 GWh used by the country’s households.

Iceland’s high level of geothermal and hydroelectric power means these mining operations have a low environmental impact. However, the same can’t be said of the largest bitcoin miner in the world: China.

While it has an abundance of hydropower and an increasing renewable capacity, a large amount of China’s electricity still comes from coal – 72% of its total generation came from the fossil fuel in 2015. This raises concerns around the environmental impact of bitcoin’s increasing electricity needs.

Digiconomist estimates the emissions of just one large-scale, coal-powered bitcoin mining operation (e.g. the operation in Ordos) could fall between 24-40 tonnes of carbon dioxide (CO2) per hour – roughly the same as flying a full Boeing 747-400 for the same period.

However not everyone is convinced the network is as energy intensive as reports suggest, and part of the challenge is that – despite knowing how many bitcoins are in existence – there’s no precise way of knowing how much mining is going on.

What is known, however, is that even as cryptocurrency prices fluctuate, mining is increasing. In short, bitcoin’s incredible appetite for electricity isn’t going anywhere soon. But could it get cleaner?

Moving towards cleaner mining

Some companies are tackling the problem of making bitcoin more sustainable by bringing it off grid and linking it directly to cleaner sources of power, much like how tech companies are striking deals with local renewable suppliers when locating data centres.

Hydrominer, for example, is placing mining hardware directly into hydropower stations, while HARVEST aims to use dedicated wind turbines to power mining, which takes pressure off national grids and their electricity sources.

However, a more fundamental change could be possible: making the protocol used to create bitcoins less energy-intensive.

Ethereum, arguably the main rival cryptocurrency to bitcoin, this year switched from proof-of-work-based mining to proof-of-stake. This means coin creation is not depended on high-powered computers cranking through calculations, but instead through owners validating their stake in the cryptocurrency and ‘voting’ on block creation.

Another alternative is Chia Network, which harnesses unused hard drive storage space for blockchain verification Chia ‘farmers’ for offering storage space for the network.

Both have significant ground to cover to catch the market leader, however, so the more pressing question remains: What’s next for bitcoin? And what will happen as the number of available bitcoins decreases?

The future of bitcoin

Like gold there are a limited number of bitcoins that can ever be mined – 21 million to be precise. This means the reward for bitcoin mining halves roughly every four years as they become more abundant. The next drop is scheduled for 2020 when the reward will slide to 6.25 BTC.

But this doesn’t mean they’re getting easier to mine. In fact, it is growing increasingly difficult, and this means more computer power and a need for even more electricity, which in turn means higher overheads.

A report from JP Morgan estimates the price of mining a single bitcoin has grown tenfold in the last year to $3,920,  a change that could send miners in search of cheaper utilities. More than this, the added stress on grids could lead to a growth in dirtier (and cheaper) fossil fuels which can generate and power mining operations around the clock.

This could mean that as mining becomes more difficult and rewards drop, it will be controlled by fewer, larger-scale operators which can absorb the spiraling costs. Either way, it’s expected they will be forced to reduce their electricity consumption (or at least the cost of it) to remain economical as the rewards they earn cover less of their expenses.

Ultimately, however, if cryptocurrency is set to play a positive role in our future it must become less electricity intensive and work with evolving energy systems to be as sustainable and progressive for the environment as it could be for the global economy.

The history of the pylon

16 February 2018

Electrification

Pylons are one of the most recognisable and perhaps divisive symbols of Great Britain’s electricity system.

There are plenty who decry these metal giants as blotches strung across the country’s green and pleasant landscape. But time has turned the 1930s designs of Great Britain’s pylons into something of a modernist classic, even beloved by some.

What pylons symbolise, however, is more than just the modernisation of the country in the first half of the 20th century. They also represent the promise of safe and reliable electricity for all. There are now more than 90,000 pylons across Great Britain and while the energy system continues to evolve, pylons have changed little since they first went up outside Edinburgh in the 1920s. 

Miesbach to Munich

The first successful attempt to transmit electricity over long distances using overhead wires took place in 1882. German engineer Oskar von Miller and his French colleague Marcel Deprez successfully transmitted 2.5 kilowatts of electricity 57km along a telegraph line.

The simple iron line transmitted a 200 volt current from a steam engine-powered generator near Miesbach to the glass palace of Munich, where it was used to power the motor for an artificial waterfall. The line failed a few days later, and even though it may be a world away from today’s 800,000 volt ultra-high voltage transmission lines, this first trial laid the foundation for the way we move energy today.

Egypt to Edinburgh

Jump to 1928 and there was something new arising on Edinburgh’s horizon. The first “grid tower” was erected here on July 14th as part of the recently established Central Electricity Board’s ambitious project to create a “national gridiron”.

Connecting 122 of Great Britain’s most efficient power stations to consumers was a mission that required 4,000 miles of cables, mostly overhead. Sir Reginald Blomfield was called in to tackle this grand challenge.

Blomfield adopted a design submitted by the American firm Milliken Brothers for the “grid towers” that would criss-cross the country. A staunch anti-modernist – as he made clear in Modernismus, his attack on modern architecture – Blomfield looked to ancient Egypt to name his steel towers.

In Egyptology, a pylon is a gateway with two monumental towers either side of it. These represented two hills between which the sun rose and set, with rituals to the sun god Ra often carried out on the structures. It was an epic name to match the grand ambitions of creating a national grid.

By September 1933 the last of the initial 26,000 pylons that made up the National Grid were installed, less than a third of the 90,000 that make up the system today. The grid was now ready to operate, on time and on budget.

Around the world to underground

As the energy system continues to evolve Great Britain’s pylons are changing too. In 2015, the National Grid unveiled a new Danish-designed pylon that shifts away from the classic industrial tower to a T-framed ski-lift style model designed to minimise the visual impact of the pylons on the landscape.

Another approach also being adopted is burying cables underground. The process of digging tracts and burying cables for thousands of miles could cost as much as £500 million but could help preserve areas of natural beauty while ensuring the whole country has access to the safe and reliable electricity it has come to expect.

As with all change, these announcements have caused a surge in nostalgia for the pylon remembered from childhood car journeys across the country.

Around the globe electricity pylons are now ubiquitous and are being pushed to new technological limits. In 1993 Greenland became home to the longest stretch of overhead powerline between pylons in the Ameralik Span, while China’s Zhoushan Island Overhead Powerline Tie set the record for the world’s tallest pylons in 2010 with two 370-meter towers.

Despite the advancements, it’s notable how little these structures have changed from the those first installed around the world. The proposed humanoid sculptures of Icelandic architecture firm Choi+Shine bare a resemblance to the original skeletal towers of the 30s. And it shows just how successful those original pylons have been at delivering much-needed electricity to homes and businesses around the country.

What will electricity look like in 2035?

14 February 2018

Electrification

The year is 2035. Cars cruise clean streets without the need for a driver, our household appliances are all connected and communicate with one another, and all of it is powered by electricity – specifically low-carbon electricity.

It’s been 10 years since Great Britain’s last coal power station shut down, and across the country wind turbines are generating more electricity than fossil fuels and nuclear energy combined, pushing carbon emissions to a new low.

This isn’t a vision of a green-minded sci-fi novel, this is the forecast for Great Britain in less than 20 years’ time. This sustainable, low-carbon future of 2035 is a significant evolution from today in 2018 and it comes despite a rising population, a continued shift to urban living and an expected rise in power demand. 

Great Britain gets power hungry

If we transport back to the here and now of the late 2010s, it would be easy to expect electricity demand to drop by 2035. In fact, since 2005 electricity demand has been on a steady decline as a result of more efficient appliances and the decline of heavy industry.

By the mid-2020s, however, this trend is expected to reverse. But with the likelihood that appliances will grow more efficient and no sign of heavy industry coming back to British shores, what will drive this growing demand?

Two of the major contributors will be the electrification of transport and the heating system. With the government setting 2040 as the end date for the sale of diesel and petrol vehicles, preparations are already underway for a fully electrified transport network – but it won’t just be restricted to roads.

Train networks and even potentially planes could switch from fossil fuels to electric, increasing demand from the transport sector by 128% between 2015 and 2035. Electric vehicles (EVs) alone are predicted to add 25 terawatt hours (TWh) of electricity demand by 2035, according to a report by Bloomberg New Energy Finance. However, this will be dependent on significant investment in the necessary charging infrastructure to enable a decarbonised transport network across the country.

Added to this will be extra demand from a shift in how we heat our homes. If planning goes ahead and pilot projects are completed, low-carbon, electric heating is expected to begin rolling out in the next decade and will involve the phasing out of gas boilers in favour of electric heat pumps. But as with EV adoption, this will require major government investment and incentives to grow electric heating beyond the 7% of UK homes that use it today.

An electrified heat network will add a greater strain on the electricity system, particularly in winter months when demand is high. The result is a forecast increase of 40 GW in demand during peak times – the mornings and the evenings.

These peak times for electricity consumption will be the greatest test for the grid as intermittent renewables meet more and more of the country’s demand. It raises the question: how we will cope with cold, still and dark November evenings? One solution is the growing role of large scale electricity storage.

By 2035 technological advances are expected to bring electricity storage to 8 GW of installed capacity – double the size of Drax, the UK’s biggest power station. It is also likely that the abilities of EVs as electricity suppliers (delivering excess electricity back to the grid once plugged in overnight) will play an increasing role in meeting demand.

But to ensure this is possible, it will require advances in another sector with a great impact on our power system: technology. This is not just about how technology could enable advances, but how much electricity it’s likely to use.

The internet of everything and a smarter grid

By 2035, chip manufacturer ARM predicts there will be more than one trillion internet of things (IoT) devices globally. This smart technology will be able to turn everything from your morning coffee maker to your bed into intelligent machines, gathering masses of data that can be used to optimise and personalise daily life.

Powering all these devices, let alone the vast plains of servers holding all the data they gather, is one of the great challenges for the IoT industry. However, as much as smart devices will demand energy, they will also help save it.

Thanks to smart, connected devices, traffic lights will turn off when there are no cars, offices will turn off lights when there is no one in a room and homes will understand your energy needs better and tailor appliance usage to your habits. At a larger scale, the introduction of artificial intelligence will allow the entire grid to connect and work in harmony with every one of the billions of devices taking energy from it.

A fully-intelligent system like this will allow grid operators to smooth out peaks in demand by, for example, charging EVs overnight when there is less demand. It means that while there will be an overall greater demand for electricity in 2035, the ‘shape’ of demand may differ from the accentuated peaks of the current system.

Renewable reaction to demand

At its heart, the increasing electrification of our transport, utilities and technology has been driven by a few specific goals, one of which is lowering our reliance on fossil fuels and reducing carbon emissions. It’s positive, then, that all projections towards 2035 have us making significant strides towards this vision.

Coal will have been completely removed from the electricity system, while gas generation will drop to just 70.8 TWh – down from the 112.2 TWh expected in 2018, according to Bloomberg’s forecast. In its place, wind will become the greatest source of our electricity producing 138.5 TWh in 2035, up from 52.3 TWh in 2018. The watershed year for wind power will come in 2027 when wind first overtakes gas to become the biggest contributor to the grid thanks to significant increases in capacity.

Nuclear will still play an important role in the energy mix, contributing 45.8 TWh, while solar will more than double in generation from 12 TWh in 2018 to 25 TWh in 2035 – the same amount of power produced by all of California’s solar panels in 2016.

The results of this continued move to lower carbon sources will be significant. Carbon emissions from electricity in 2035 are expected to be 23.81 gCO2/MJ (grammes of carbon dioxide per megajoule) – less than half what is expected in 2018. And while there will be many major changes in the electricity system over the next 17 years, it is this that is perhaps the most important and optimistic.

5 incredible numbers from the world’s largest biomass port

26 January 2018

Sustainable bioenergy

Since its origins the Port of Immingham has held close links with the UK’s rail and energy networks.

It was the Humber Commercial Railway and Dock company, along with the Great Central Railway, that first established the dock, completing it in 1912 to serve its primary purpose of exporting the most important fuel of the time: coal.

Today, Immingham is the UK’s largest port by tonnage, and while these transport connections endure, they’ve changed with the times. The port is now connected to modern rail infrastructure and helps run a renewable energy system.

Immingham is one of a number of UK ports that receives shipments of wood pellets which are used to generate renewable electricity at Drax Power Station in Yorkshire. With 20,000 tonnes of wood pellets arriving at Drax every day, here are the numbers that tell the story of how the port of Immingham keeps more biomass coming in than any other in the world:

£135 million revamping for renewables

The port began to get serious about renewable energy in 2013 when an investment of around £135m kick-started the creation of the Immingham Renewable Fuels Terminal – the largest biomass handling facility in the world.

Developed by the Associated British Ports as part of a 15-year deal with Drax, the revamp of the former coal port saw an update of its unloading, storage, rail and road facilities to make it biomass-ready.

Getting those 60,000 tonnes of biomass pellets from ship to train to Drax requires tight supply chain systems designed especially for this task.

2,300 tonnes of biomass unloaded every hour

A key component of Immingham is its continuous ship unloaders. Replacing the port’s grab cranes in 2013, these two structures use a combination of suction and an Archimedes screw to discharge 2,300 tonnes of biomass an hour from docking ships.

The continuous unloaders are bespoke for Immingham and designed to keep operating at a constant rate as the Humber’s tide rises and falls. Biomass is drawn up through the unloaders to a conveyer that then takes it all the way from the jetty to one of the port’s eight silos.

120 Olympic-sized swimming pools of storage

Unlike coal, which can be stored in the open air, biomass must be kept dry. Immingham stores wood pellets in eight silos, each capable of holding 25,000 tonnes of biomass.

With the port doubling its storage space from four silos in early 2016, the site’s total capacity now comes in at 336,000m3 – the equivalent of more than 120 Olympic-sized swimming pools.

Here the biomass can be stored for any time between a couple of days and a couple of months, depending on Drax’s demand.

72 trains heading to Britain’s biggest power station every week

The next leg of the journey for the wood pellets sees them moved along the conveyer to board Drax’s specifically designed trains.

Immingham’s rail facilities and Drax’s train wagons were developed to automate the loading process for maximum efficiency. Trains slow down to half a mile per hour as they enter the loading bay where sensors and magnets open the hatch doors of the wagons and close them when they’re full.

The automation of this process allows a 25-wagon train to be filled in just 37 minutes. In total, 12 trains can pass through each day, meaning the port can send 72 trains to Drax every week.

With each hopper’s full load at 71.6 tonnes of compressed wood pellets, each train can carry between 1,700 and 1,800 tonnes. It takes the total biomass reaching the power station from Immingham to a maximum of 130,000 tonnes each week.

£400 million added to the local economy

Drax’s contribution to the Yorkshire and Humber region includes 3,650 jobs and a £419.2 million economic impact.

This is primarily the result of the impact made by Drax Power Station to the region, however, its support of other businesses along its supply chains means its economic contribution is felt far beyond its Selby site.

In 2016, Drax indirectly supported 1,800 jobs in Yorkshire and the Humber region at facilities such as Immingham. Its indirect economic contribution came to £117 million, as the region’s biomass industry became increasingly important.

Find out about another major UK port that has been transformed thanks to renewable energy. How does biomass get shipped to the UK? Read the story of one of the US ports sending wood pellets to UK shores.

How electricity is made

25 January 2018

Power generation

Every morning we take electricity as a given. We switch on lights, charge phones and boil kettles without thinking about where this power comes from.

The electronic devices and appliances that make up our daily routines are not particularly energy intensive. Boiling a kettle only uses 93 watts, toasting for three minutes only requires 60 watts, while cooking in a microwave for five minutes takes 100 watts.

However, when people are waking up and making breakfast in almost 30 million households around the UK, those small amounts soon create a significant demand for electricity. On a typical winter’s morning, this combined demand spikes to more than 45 gigawatts (GW).

So this is what it takes to power your breakfast – from the everyday toaster in your kitchen backwards through thousands of miles of cables to the hundreds of thousands of tonnes of machinery in wind farms, hydro-electric dams and at power stations such as Drax where electricity generation begins.

The grid 

The journey starts in the home where all our electricity usage is tracked by meters. These are becoming increasingly ‘smart’, displaying near real-time information on energy consumption in financial terms and allowing more accurate billing. There are already 7.7 million smart meters installed around the UK, but that number is set to triple this year, paving the way for a smarter grid overall.

What brings electricity into homes is perhaps the most visible part of the energy system on the UK’s landscape. The transmission system is made up of almost 4,500 miles of overhead electricity lines, nearly 90,000 pylons and 342 substations, all bringing electricity from power stations into our homes.

Making sure all this happens safely and as efficiently as possible falls to the UK’s nine regional electricity networks and National Grid. Regional networks ensure all the equipment is in place and properly maintained to bring electricity safely across the country, while National Grid is tasked with making sure demand for electricity is met and that the entire grid remains balanced.

The station cools down

One of the most distinctive symbols of power generation, cooling towers carry out an important task on a massive scale.

Water plays a crucial role in electricity generation, but before it can be safely returned to the environment it must be cooled. Water enters cooling towers at around 40 degrees Celsius, and is cooled by air naturally pulled into the structure by its unique shape.

This means those plumes exiting from the top of the towers are, rather than any form of pollution, only water vapour. And this accounts for just 2% of the water pumped into the towers.

Drax counts 12 cooling towers, each 114 metres tall – enough to hold the Statue of Liberty with room to spare. Once the water is cooled it is safe to re-enter the nearby River Ouse.

The station’s bird’s-eye view

The control room is the nerve centre of Drax Power Station. From here technicians have a view into every stage of the power generation process.  The entire system controls roughly 100,000 signals from across the power station’s six generating units, water cooling, air compressors and more.

While once this area was made up of analogue dials and controls, it has recently been updated and modernised to include digital interfaces, display screens and workstations specially designed by Drax to enable operators to monitor and adjust activity around the plant.

The heart of power generation 

At the epicentre of electricity generation is Drax’s six turbines. These heavy-duty pieces of equipment do the major work involved in generating electricity.

High-pressure steam drive the blades which rotates the turbine at 3,000 revolutions per minute (rpm). This in turn spins the generator where energy is converted into the electricity that will eventually make it into our homes.

These are rugged pieces of kit operating in extreme conditions of 165 bar of pressure and temperatures of 565 degrees Celsius. Each of the six turbine shaft lines weighs 300 tonnes and is capable of exporting over 600 megawatts (MW) into the grid.

One of the most important parts of the entire process, turbines are carefully maintained to ensure maximum efficiency. Even a slight percentage increase in performance can translate into millions of pounds in savings.

Turning fuel to fire

To create the steam needed to spin turbines at 3,000 rpm, Drax needs to heat up vast amounts of water quickly and this takes a lot of heat.

The power station’s furnaces swirl with clouds of the burning fuel to heat the boiler. Biomass is injected into the furnace in the form of a finely ground powder. This gives the solid fuel the properties of a gas, enabling it to ignite quickly. Additional air is pumped into the boiler to drive further combustion and optimise the fuel’s performance.

Pulveriser

How do you turn hundreds of tonnes of biomass pellets into a powder every day? That’s the task the pulveriser take on. In each of the power plant’s 60 mills, 10 steel and nickel balls, each weighing 1.2 tonnes, operate in extreme conditions to crush, crunch and pulverise fuel.

These metal balls rotate 37 times a minute at roughly 3 mph, exerting 80 tonnes of pressure, crushing all fuel in their path. Air is then blasted in at 190 degrees Celsius to dry the crushed fuel and blow it into the boiler at a rate of 40 tonnes per hour.

The journey begins: biomass arrives

Biomass arrives at Drax by the train-load. Roughly 14 arrive every day at the power station, delivering up to 20,000 tonnes ready to be used as fuel.

These trains arrive from ports in Liverpool, Tyne, Immingham and Hull and are specially designed to maximise the efficiency of the entire delivery process, allowing a full train to unload in 40 minutes without stopping.

The biomass is then taken to be stored inside Drax’s four huge storage domes. Each capable of fitting the Albert Hall inside, the domes can hold 300,000 tonnes of compressed wood pellets between them.

Here the biomass waits until it’s needed, at which point it makes its way along a conveyor belt to the pulveriser and the process of generating the electricity that powers your breakfast begins.