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The 4 most common myths about renewables

6 October 2016

Power generation

Renewables make up more of the world’s energy mix than ever before. And yet, misconceptions about these new or alternative technologies – such as biomass, solar and wind – are common.

Some of these concerns are – for the time being – partly justified, some completely subjective, and some are demonstrably wrong. Here’s a closer look at the most pervasive myths and what truth there is behind them.

Renewables are unpredictable

An oft-repeated misconception is that renewables aren’t a full-time solution to our power needs. It’s true that solar isn’t generated at night and wind turbines don’t operate in still weather, but the canon of renewables is bigger than its two most well-known technologies.

Tidal power still depends on environmental factors, but tides are much more predictable than wind or sunlight. For countries lucky enough to have ready access, geothermal power – which uses heat from the earth’s core to power generators – is even more reliable.

Biomass solutions, such as compressed wood pellets, are a fuel-based power source, meaning they are flexible so can be used to generate electricity on demand and operate as a base-load power option, much like coal or gas. At Drax Power Station renewable electricity is generated on demand using compressed wood pellets and delivered to the National Grid 24-hours-a-day.

Now, thanks to advances in weather forecasting, the National Grid can plan ahead to balance the system with other renewable and low carbon technologies when the sun isn’t shining and the wind isn’t blowing. Just a few years ago the primary fall back was relying on coal power stations to pick up any slack.

It might not be possible to power the world entirely with one renewable source, but the right mix of technologies could provide an answer to the question of how to ensure a stable and secure low carbon energy supply.

Heavenly Scene Stormy Skies

Renewables are expensive

There is some truth in this, but it’s important to note that these costs are falling. Many of the high costs associated with renewables have been down to a lack of infrastructure investment.

A number of the components required in construction of structures like wind turbines and solar panels are expensive. And, as many renewable facilities need to be located in different areas to existing traditional facilities, extensive power grid extension is often needed. But these are problems that once set up, should bring down the costs of renewables such as solar and wind.

Setting up biomass-powered facilities is considerably cheaper. Compressed wood pellets can be used in upgraded coal power stations, so there’s no need for expensive new connections to the high-voltage electricity transmission system.

There are even ways renewables could bring about cheaper power for consumers. Research commissioned by Drax and published by NERA Economic Consulting and Imperial College London found that, if the same government support offered to some renewable technologies (i.e. wind and solar) were open to all (such as biomass), consumers could see potential savings of £2 billion on their energy bills.

Renewables are ugly

While this isn’t necessarily an opinion shared by everyone, it is one that is often cited. Onshore wind farms often draw the most ire, but they aren’t alone. Large investments are being made in offshore wind farms, which are both more discrete and better positioned to take advantage of stronger offshore currents.

And hydropower projects like dams and tidal barrages can in the long term create whole new habitats, ecosystems and leisure facilities in the form of artificial lakes and surrounding forests.

Nobody uses renewables

In 2015, 99% of Costa Rica’s electricity came from renewable sources, including hydro, geothermal, wind, biomass and solar. Closer to home, Sweden draws more than 50% of its electricity from renewable sources, including 22% from bioenergy – 90% of which comes from forestry.

In the UK, renewables use is steady and rising, accounting for 25% of all electricity generated domestically in 2015. In the first half of 2016, 20% of the UK’s renewable power was supplied by Drax. Contrast those figures against coal, which in the UK declined from supplying 30.8% of UK power needs in Q1 2015 to just 15.8% in Q1 2016, and our increasing use of renewables is even more evident.

Consumers have been buying 100% renewable electricity tariffs from companies such as Good Energy for more than a decade. Businesses are increasingly getting in on the act too. Two thirds of the power generated by Drax in the first half of 2016 was sold directly to companies via Drax Group’s business electricity supplier, Haven Power.

And with campaigns such as RE100 challenging the world’s biggest firms to commit to renewable-only power, household brands such as Ikea, M&S and Google are either already 100% renewable or only a few years away.

Misconceptions about renewables will remain as long as we’re still in the transition out of fossil fuel use. But the industry has made huge strides from where it was just 10 years ago.

Thanks to better, more affordable technology, an increasingly friendly corporate sector, and a greater awareness of environmental issues at large, these products and services will continue to improve, grow and increasingly becoming more mainstream.

An alternative way to heat your home

Sustainable bioenergy
Beautiful old village landscape nestled amongst hills in Lake District

There are things we, as a modern society, expect in our homes: running water, electricity at the touch of a button, heating for when temperatures drift south.

All are ubiquitous in the UK, serviced by large networks that deliver these resources on demand. But there are some areas in the country that exist apart. In the UK there remains a large proportion of homes off the gas grid.

Without the benefits of easy-to-access gas and gas boilers, these households rely on other forms of heating often fuelled by expensive and high-carbon fuels like oil or liquid petroleum gas (LPG).

But there are alternatives to these, and of those fuels, biomass is not only an increasingly affordable one, but a cleaner one, too.

How do you heat your home with biomass?

Biomass boilers work in much the same way that a gas powered one does. They use fuel to generate a heat source that then heats water which is passed through radiators and into your household’s hot water supplies. Whereas the majority of boilers in the UK use gas as a fuel source, biomass boilers run on natural wood products, such as compressed wood pellets.

It’s an efficient and effective way of heating homes and in Europe it’s a common one. In Sweden, 1,400,000 tonnes of pellets were used in 2014 for heating.

Compare that with the UK’s 300,000 – in a country with six times the population – and the difference is stark. Biomass covers more of Europe’s energy requirements than any other, but in the UK we’re falling behind continental averages.

A cleaner, cheaper alternative

Wood is a simple renewable fuel. A growing tree absorbs carbon dioxide out of the atmosphere, which is released when the wood is used to generate energy in the form of heat or electricity. New trees are planted to replace the old ones and the carbon dioxide is absorbed all over again. Thanks to this cyclical process, biomass fuel is sustainable.

This makes compressed wood pellets a more climate-friendly fuel source than the fossil fuels of the past such as diesel and oil. As well as being renewable, there are financial benefits too: a wood-fuelled biomass boiler offers significant savings when compared with electric heating.

Support towards a cleaner future

The Government has recognised the importance of technologies such as biomass-fuelled boilers in achieving a lower carbon future. The Renewable Heat Inventive (RHI) programme was introduced to provide incentives to homeowners, landlords and commercial customers for installing generators of renewable heat such as wood pellet boilers.

Its objective is to try to achieve the target of ensuring that 12% of the UK’s heating comes from renewable sources by 2020. Currently it makes up just 5% of the total.

But with improving technology and a more regular supply of biomass fuel – such as that offered by AMP Clean Energy [previously Billington Bioenergy] to domestic customers – domestic wood pellet heating could become something that’s not just a niche option, but a serious alternative to off grid homes.

How a new industrial revolution in green energy is transforming the North once again

Sustainable business

The North of England has long been a proving ground for the kind of engineering innovations that have transformed the world. The heartland of the First Industrial Revolution, it is now at the centre of a new revolution focused on clean energy production and sustainable power, led by organisations like Drax.

Europe’s largest decarbonisation project

Over the last decade, Drax has been carrying out a major high-tech engineering and infrastructure project to upgrade half its generating units to use sustainable biomass in place of coal.

These converted units now produce enough electricity to power Birmingham, Leeds, Sheffield, Liverpool, Manchester and Newcastle – all using compressed wood pellets, cutting carbon emissions by more than 80%.

But more than just having environmental benefits, it’s provided a huge boost to the economy.

Boosting the UK economy

In 2015, Drax contributed more than £1 billion to the UK’s GDP and supported some 14,000 jobs across the country.

“The economic benefit has reached all parts of the country,” says CEO Dorothy Thompson. “We’ve been the catalyst for rejuvenation and growth across the Northern Powerhouse, with port expansion on the coasts of East Yorkshire, the North West and North East.”

This boost was particularly significant in the North, where Drax generated over £620 million for the local economy.

Innovation driving a better future for Britain

It’s these kinds of innovative upgrades that are helping to tackle the urgent environmental challenges that our society faces as we make the transition to lower carbon and renewable power, and changing the way we think about producing energy in the UK.

Having nurtured the Industrial Revolution, today the North of England is again the focus of a major paradigm shift. Where once coal fields and smoke stacks dominated the local landscape, now Drax’s giant biomass storage domes speak of a new future for the region, for the UK, and for renewable energy production as a whole.

To find out more about how Drax has benefited the UK’s economy, please visit https://www.draximpact.co.uk/

Inside the dome

Sustainable bioenergy

There are four storage domes at Drax Power Station and each of them can hold 80,000 tonnes of compressed wood pellets. It’s these biomass pellets, a sustainable fuel, that Drax is being upgraded to run on and produce renewable electricity.

Wood pellets are an incredible fuel that can match coal for efficiency – the challenge is you just need more of them as the density and calorific value of coal is greater. However, storing such large quantities in a confined space presents risks that have to be managed, 24/7.

Atmospheric control

The crucial difficulty with storing the pellets is their chemical volatility. Wood, which the pellets are made from, emit carbon monoxide (CO). In a confined space such as the storage dome, this CO can build up and – due to CO’s extreme flammability – require the entire internal atmosphere to be regulated by a set of highly sophisticated engineering solutions.

As long as materials are emitting more heat into the atmosphere than they are storing in themselves, there is no risk of combustion. A single wood pellet in a fuel store poses no fire risk. Nor does a small pile. But when thousands upon thousands are piled together, the pressure builds up and causes the pellets to heat up.

Gradually, the rate of temperature increase speeds up, and before you know the flashpoint threshold has been crossed and there’s potential for danger.

However, remove or limit the oxygen supply in the silo and purge the CO that’s emitted from the pellets, and the risk of a thermal event is substantially reduced. The challenge for the engineers at Drax constructing the domes was finding a way to manage temperatures within the dome.

Neutral nitrogen

To do this they created a system to automatically inject nitrogen into the storage dome. While nitrogen isn’t a truly inert gas, it is much less reactive than CO and oxygen.  With this pumped into the dome’s atmosphere it is a much safer environment.

To get a steady supply of nitrogen, regular air from our atmosphere – which is 78% nitrogen – is passed through a molecular filter, which removes the larger oxygen molecules. The gas collected at the other end is 96% nitrogen.

This nitrogen-rich air is then injected from underneath the dome and continually distributed around it. Not only is this a fire prevention method, but also a firefighting one that can be pumped in larger quantities in the event of combustion. Separate to the above measures which are there to manage fuel temperatures, the dome is also fitted with a carbon dioxide (CO2) injection system and water deluge system which are there as fire extinguishing precautions.

The big ear inside the dome

The next problem facing the designers was how to accurately monitor the quantity of compressed wood pellets inside the dome. To achieve this, each dome is fitted with a sonar system – which sounds a bit like a chirping bird – that provides continuous feedback on how full the dome is.

The sonar monitoring system provides level, profile and volume information which is translated into a 3D image of the stored biomass. This method of volumunetric measurement allows the operators to view and monitor in ‘real time’ the effects of their actions when filling and unloading domes, so they can target specific areas particularly when unloading and for fuel accounting purposes.

Other tools and tricks

Five thermocouple arrays measure the pile temperature and provide feedback in real time to the operators to allow them to assess the status of the dome and effectively plan material filling and reclaim. Gas monitors measure the levels of CO and CO2 as well as O2 depletion within the head space of the dome.

A dome breather vent (a two way acting valve, which as its name suggests, allows the dome to breathe) is fitted to the top of the dome and acts as a vacuum breaker maintaining a relatively even pressure allowing air in during unloading and releasing head space gasses during nitrogen inserting.

The final piece of the atmospheric control puzzle is regulating pressure. At the top of each dome is a controllable aperture called a slide gate which is closed unless the dome is being filled to allow material to enter. A dome aspiration system is installed here to filter and remove displaced air from within the head space during filling, but also allow a route for CO and other offgassing products to escape.

All the hidden systems within these four huge white domes allow the operator to effectively control their atmospheric conditions and crucially to store massive amounts of potentially volatile biomass safely on site.

Find out more about these giant storage domes – read the story about how they were constructed. 

The power industry in 2016: Where are we now?

Power generation

Britain is in the middle of a transition. While at one point it was the centre of the global coal industry, it’s now pushing further towards renewable resources. But 2016 has been a tumultuous year marked by political changes that have sent shock waves through the whole country. The energy industry is no exception – but that is not to suggest it’s on shaky ground.

Here we look at some of the year’s major events and how they’ve affected the energy landscape.

Leaving Europe

Britain’s vote to leave the EU could have a major impact on the domestic energy landscape. Europe has played a central role in setting emissions targets for power stations, promoting renewable technologies and trading carbon. The UK also benefits from being in the Single Energy Market, where energy market rules and regulations are harmonised across a number of European countries. A post-Brexit resolution to these issues is likely to remain uncertain for some time.

As Drax CEO Dorothy Thompson told a conference in Florida in late September:

“It will take a number of years for the UK to actually exit the EU, and we think politicians on all sides will push for an orderly departure.”

Implementing the Paris Agreement

Following last year’s Paris Agreement on Climate Change, the UK Government demonstrated its commitment to being a world leader in clean energy by setting its Fifth Carbon Budget. The Budget, initially proposed by the independent advisory body the Committee on Climate Change, sets a cap on the UK’s greenhouse gas emissions for the period 2028-2032. The cap is ambitious and would require the UK to reduce its emissions to a level 57% lower than they were in 1990. The Government is working on a new Emissions Reductions Plan that will map out how it intends to meet this goal and accelerate decarbonisation in the power, heat, transport and agricultural sectors.

Political change

The reshuffle following Theresa May’s election as Conservative Leader and therefore Prime Minister also marked the end of the Department of Energy and Climate Change (DECC), previously responsible for overseeing the country’s energy policy and its transition towards greener, more renewable energy sources. While the decision raised concerns in some quarters over the Government’s commitment to decarbonisation, placing energy policy at the heart of a modern industrial strategy under the new Department for Business, Energy and Industrial Strategy could reap dividends in the long-term.

Green light for Hinkley Point

Perhaps the single most highly scrutinised energy issue of the year, and an indirect fallout of the summer’s political drama, was the Government delaying its approval of the planned Hinkley Point C nuclear power station.

The project backed by EDF and Chinese investors was, when first announced by the French government-controlled energy company in 2007, due to be generating electricity by the festive period just a decade later.

Jumping ahead to 2016 and having been approved by Theresa May two months’ later than the industry anticipated, expectations are that the development is unlikely to cook its first Christmas turkey until 25th December 2025 – at the very earliest. This raises serious questions over what will fill the gap left by aging nuclear power stations that are due to close over the next few years. This said, delays to Hinkley Point C present an opportunity for alternative energy sources such as offshore wind, solar and compressed wood pellets to make their case to work together as smart, affordable solutions that could be in place well ahead of 2025.

Whole system costs

The research and thinking around the issue of whole system costs continued to grow. A series of reports from NERA Consulting and Imperial College London showed that intermittent technologies such as wind and solar make managing the national energy grid more expensive in the absence of flexible, dispatchable technologies like biomass. It is only when these hidden costs are taken into consideration that we can truly understand the affordability of different energy technologies.

Recognising the importance of this issue to good policy making, the Government has commissioned its own research on whole system costs, which is due to be published later this year.

Coal closure

2016 saw some important landmarks in Great Britain’s history as a coal-using nation. A 12-hour stretch in May this year was the first time since 1882 – the year GB’s first coal-fired power station went online – that the country was powered for more than half a day completely by other fuels.

Plans outlined last year by then Energy Secretary Amber Rudd had aimed to ban unabated coal power stations by 2025. This year has already seen coal-fired casualties. Full or partial closures of five major coal burning power plants in Great Britain have taken place in 2016: Ferrybridge, Longannet, Rugeley, Fiddler’s Ferry (some units of SSE’s north west coal station will remain active until next year) and Eggborough (re-opened in late September for the winter 2016/17). By the end of 2016, the equivalent of between two and three Hinkley Cs (8 GW) will have come off the system.

While Rudd’s plans still stand, delays to Hinkley Point C and a lack of new flexible power stations being built in Great Britain means that the Government will need to think carefully about how to get coal off the grid in an orderly fashion to avoid a capacity crunch in the early 2020s.

Ancillary = essential; Capacity crunched

Despite the strides made by renewables over the course of the year and the recent boon to the nuclear sector’s future, GB power infrastructure badly needs flexible fuels. The ability to generate more power – or less – in mere seconds when the country demands it is becoming increasingly important with the growth of wind and solar power.

As more offshore wind arrays are constructed and solar farms and roofs proliferate, there are an increasing number of gaps in our electricity supply being filled by power sources that can be dialled up and down when the wind doesn’t blow and the sun doesn’t shine. While Drax and two planned power projects in the North East of England (Lynemouth and MGT Teeside) are turning to a coal-to-biomass conversion and a new build biomass combined heat and power plant to meet these needs, the Government continues to look for ways to encourage companies to build new gas power stations as well as emerging battery storage technologies. A critical route to incentivising these technologies is the not-very-aptly-named ancillary services market. It involves the high voltage electricity system operator in Great Britain, the National Grid, buying services to ensure the lights stay on, the increasingly electric transport sector keeps running and our high-tech world of work stays online.

Energy future

So far there have been some very big changes over the course of the year. However the energy ecosystem in Great Britain should be robust and flexible enough that the transition from coal to low carbon and renewable technologies in the future should be a secure and affordable one. This will require a mix of smart solutions. A key enabling technology will be coal-to-biomass upgrades that can run as both baseload and flexible generators.

5 things you never knew about forests

Sustainable bioenergy
Background. Fir tree branch with dew drops on a blurred background of sunlight

Forests and the products we derive from them are one of the most ubiquitous aspects of human civilisation. Despite the rapid pace of modern life, that isn’t changing.

Forest still covers 30% of the world’s land and in the UK more than an estimated 55 million m3 of wood was used in 2015 – either directly through furniture, books or hygiene paper, or indirectly, in infrastructure like fences, railways or through biomass electricity generation.

Behind all this lies the forest and the industry surrounding it. But how much do you really know about forests?

In some regions forests are increasing

Mention forestry, and there are plenty of people who make the jump to the activities of unscrupulous developers and deforestation. But while forest land is declining worldwide (in fact, we’ve lost 129 million hectares since 1990), the good news is the rate of decline is dropping sharply, down 50% across the same period.

A lot of this is thanks to growing environmental awareness, responsible forestry management and reforestation around the world. 10,000 hectares of new woodland was created in the UK in 2014 and in the USA, where a third of all land is forested, forestland has been consistently increasing over the last 25 years. There’s been an increase of roughly 7.6 million hectares between 1990 and 2015.

Vigorously growing forests absorb CO2 faster

It’s well known that trees are “the lungs of the earth”, but not all trees or ages are equally effective at absorbing the greenhouse gas CO2. A growing, younger forest is a better sink for carbon dioxide than a forest that is mature and stable. This has implications for the way these resources are used – notably when it comes to the sourcing of material for compressed wood pellets.

Whereas coal releases carbon that has been trapped underground for millions of years, wood releases carbon captured within its lifetime, making it a very low carbon fuel once manufacturing and transportation are factored in. The technique is to harvest trees when they have stopped growing at a fast rate, use the wood for forest products such as timber, pulpwood or compressed wood pellets for energy and replant the area with new, high growth potential trees. The result is a forest with a steady stream of CO2-hungry young trees and a steady stream of renewable raw material.

Forests can stop floods

 A study led by the Universities of Birmingham and Southampton and funded by the Environment Agency, found that forests in Europe play an important role in mitigating the effects of heavy rain.

Thanks to the buffering abilities of the forest canopy and the enormous water absorption capacity of woods and forests, they can slow the flow of a sudden downpour of rain overfilling nearby streams or rivers. This water will eventually be released but slowing its movement mitigates flash flooding.

Different parts of the forest have different uses

The primary commercial product from forests is not a hard one to guess: wood. But there’s more to it than that. For construction timber, the lower, thicker parts of a tree’s trunk are used. Smaller parts of the trunk are used as pulpwood which can be used to make paper, panels or for energy. Residues from the wood processing industry such as sawdust can also be used for compressed wood pellets.

With the rise of the internet, smartphones and e-readers the paper market has been shrinking. Manufacture of high-density wood pellets helps replace demand for wood once used by the paper market, as pellets can be made using low-grade wood, thinnings and residues not used in construction or furniture.

Trees talk to each other

Until recently it was thought that trees perform most of their biological functions in isolation from each other. But biologists have learned in recent years that in fact they communicate and help each other.

Under the forest floor, trees’ roots are linked by bright white and yellow fungal threads, called mycelium. In a forest, these threads act as a kind of network, linking trees to one another.

These links enable trees to share nutrients, carbon and water. Some species of tree also increase nitrogen uptake in the soil and help to improve the conditions in which other species grow. In fact, research by the University of British Columbia, indicates that certain large, older trees that rise above the forest act as ‘mother trees’ which actively help to ‘manage’ the resources for the other trees in the forest.

Based on their findings, it seems trees not only talk to each other, but help each other grow too.

The single biggest transformation of our century

Sustainable bioenergy

At the turn of the millennium, Drax was facing a serious issue. Demand for electricity was high and increasing, but so was the desire for sources of power that were less harmful to the environment than coal, at that time Drax’s fuel.

To continue to meet demand in a cleaner and more sustainable way, an alternative approach was needed. Drax had a legacy in this field – in 1988, it was the first coal-fired power station to install flue-gas desulphurisation technology, which removes 90% of coal’s harmful sulphur dioxide (SO2) emissions.

In the two decades that followed, however, the sustainability conversation moved beyond how to make coal cleaner. Instead, the focus was finding a truly viable alternative fuel.

Finding a new fuel

In those early days, the idea of converting a fully coal-fired station to another fuel seemed outlandish to say the least.

“We made a lot of people’s heads hurt with this project,” says Drax Strategic Projects Engineering Manager Jason Shipstone. “No one had the answers. It was a bit like going for a walk but not knowing where you’re going.” Back then it was all about experimentation.

Jim Price, Alternative Fuel manager at the time, explains: “Initially, we found a few distressed cargos of wood pellets and sunflower husks that someone had ordered but didn’t want. We mixed that with coal at very low concentration.”

Price and his team found they could use the plant-based fuel alongside coal at low percentages without it detrimentally affecting the boilers. It was a long way from being a new business model, but it was a start. They spent the next year working with willow wood, a subsidized energy crop that proved difficult to turn into a fuel that could be used efficiently to power a boiler.

Then in 2005, after building a prototype plant and finding a way to pulverise the willow into a fine powder – called wood flour – and combine it with coal dust, the team hit its first key milestone. It was able to power a Drax boiler.

“That was the Eureka moment,” says Price.

“No one had the answers. It was a bit like going for a walk but not knowing where you’re going.”

A change in attitude

The response to the success was immediate. Senior management support for the project had been in place from the beginning, but now there was a change across the whole company. “People started to think maybe it can be done,” says Price.

Work continued on the project and – after more experiments – Drax eventually settled on compressed wood pellets. This form of biomass ultimately required investment in four vast storage domes that between them store 80,000 tonnes of pellets.

Then there was the issue of supply and delivery. Materials were sourced from the US, shipped to the UK, then freighted to the plant in specially designed covered train wagons, each carrying up to 7,600 tonnes.

“Everything else had to carry on as normal. This had to be seamless. We had to work the same as Drax has always worked – reliable and available,” says Shipstone.

Jason Shipstone, Drax Strategic Projects Manager, played an instrumental role in upgrading Drax.

Jason Shipstone, Drax Strategic Projects Manager, played an instrumental role in upgrading Drax.

The final hurdle

In 2009 the team overcame one of the final challenges, and successfully adapted the boilers to combust the new fuel, proving that co-firing (the process of using two fuels powering one boiler – in this case wood pellets and coal) could work. It was enough to show there was a future in wood pellets and it could work at scale.

Although nothing was fully built yet, but Dorothy Thompson, CEO of Drax, was convinced. Shipstone remembers the conversation after Thompson signed the contract to begin the transition in earnest. “’So we can do 10%. What does it take to get to 50%?’ she asked,” recalls Shipstone. His response? No problem. “It was the right answer,” he says.

Toward a coal-free future

Fast forward to 2016, and Drax is Europe’s largest decarbonisation project – reducing emissions by at least 80% of the 12 million tonnes of carbon dioxide that the three, now converted, former coal generation units would have released per year. Although only half of Drax’s six units have been upgraded from coal to use compressed wood pellets, 65% of the electricity generated at the power station is the result of a renewable, rather than a fossil fuel. Its three biomass units produce enough electricity to power the equivalent of four million homes – or more than half of all residential properties in northern England.

Given the challenges the world faces regarding the future of energy production, decisive action is required if we’re to meet carbon reduction targets. In the UK the government has voiced ambitions of phasing out coal by 2025. Drax has aims of doing it quicker. Thompson has spoken of plans that see all coal units taken off the Drax system by 2020, if not before.

The story of energy since the dawn of the Industrial Revolution has been one of fossil fuels. This simply has to change. By finding a way to ease the transition away from coal, Drax is helping to write the next chapter.

The biggest balls of electricity generation

Power generation

When making a cup of tea, it’s unlikely you consider the industrial equipment kicked into action the moment you switch on your kettle. And of all of the activity going on behind the scenes, it’s even more unlikely you think about a 1.2-tonne steel ball.

But without a number of 1.2-tonne balls and the electricity they help generate, your kettle would be nothing more than a fancy jug.

How do giant balls help to generate power?

The answer lies in the way fuels like coal and compressed wood pellets are used to power boilers and generate electricity. Drax started its life as a coal power station, but today it is in the process of upgrading to run on biomass. Progress has already been made – three of the station’s six units already run on compressed wood pellets, Drax’s biomass fuel, generating around 20% of the UK’s renewable electricity.

To generate enough power to supply 8% of the UK’s demand – as Drax does – a lot of fuel is needed. Hundreds of thousands of wood pellets are delivered to Drax every day, arriving on custom-built trains travelling from the Ports of Tyne, Hull, Immingham and Liverpool.

The pellets pass through a system of conveyor belts until they arrive at one of four massive conical storage domes, located on site in Yorkshire. Before the wood pellets can be converted into fuel, they need to be crushed: this is where the balls come into play.

The pulveriser

The wood pellets used at Drax are compressed and dried wood that is formed into small capsules the size of a child’s crayon. But, like with coal, to get the best results in the power station’s huge boilers, the material needs to be turned into a very fine powder in pulverising mills. When very fine, the fuel burns as efficiently and as quickly as a gas.

Inside each mill are 10 giant steel balls that grind down either the wood pellets or coal. Each ball is three quarters of a metre in size, made of hollow cast steel alloy and weighs roughly 1.2 tonnes – equivalent in weight to British-made Jaguar XE mid-sized saloon car or an entire football team.

And to make sure that each one is up to the task of extreme pulverisation, they need to be hard. Each one is heat treated during manufacture to make sure they’re up robust enough to consistently crush raw fuel.

The benefit of this durability is that they can readily pulverise fuel to feed Drax boilers, to power kettles across the country – a big responsibility for a big ball.

How does Europe use biomass?

Sustainable bioenergy
Family on summer Senja coast (Norway, polar day)

At the heart of Norse folklore is a figure called Yggdrasil that connects its nine worlds and gods. It’s an immensely important and holy icon, but it is not a god itself – it is an ash tree.

That the central figure of mythical Scandinavian cosmology should be something as humble as a tree is no surprise, Scandinavia is a heavily forested region. Sweden, the largest country in the area, is more than 68% forest. Wood is an inherent part of life there. For thousands of years it’s been used as a resource and a fuel, and today is no different.

Throughout much of Europe the same is true. But, while historically wood was used only for cooking, heating and light, today its use as a form of energy also includes generating electricity and heat when formed into compressed wood pellets.

Europe and wood pellets

Nearly 22 million tonnes (Mt) of wood pellets were used in the European Union in 2015, making the region the leading wood pellet consumer in the world. It is also the world’s leading producer, creating roughly half of the world’s global output – largely from European trees.

A report from the Standing Forestry Committee, set up to represent the forestry industries in EU countries, found that just 4% of the woody biomass used in the EU was imported.

Of the 22Mt used across Europe, 10.5Mt was used for heating, while 11.5Mt was used for industrial uses like fueling power plants. But in the UK, the level of wood used for fuel falls some way behind EU averages. Thanks in large part to Drax and its transition from coal to renewable wood pellet-powered electricity generation, that’s changing, but the UK still has a way to go to catch the continental average.

Where is the UK falling behind and how is wood being used to power the rest of the continent? Here, we look at some of the largest consumers and producers of biomass in Europe and how it’s being used.

Sweden

Sweden is the third highest consumer of wood as a source of energy in Europe, trailing only Finland and Latvia in its use. A key use of biomass in Sweden is powering district heating systems. In a district heating system, rather than each building or home having its own boiler, whole areas of cities are heated through a single central plant distributing heat to buildings. These plants can be powered by a variety of fuels, but many run on wood pellets or distribute the waste heat captured at power plants.

rax_europe_biomass_sweden

Germany

In 1713, an accountant and mining administrator, Hans Carl von Carlowitz, published what is considered the first ever book to look in depth at forestry management, effectively kickstarting the modern idea of sustainable forestry. In the 300 years that have passed, Germany has embraced the cultivation of wood and has made wood and biomass a fixed part of its energy makeup.

More recently, the Renewable Energy Heating Act and Market Incentive Programme was passed in 2009, which requires new building owners to provide a percentage of their heat from renewable sources, including wood-fired boilers. The aim is to increase the country’s share of renewable heat to 14% by 2020.

Europe, Biomass, Germany

Finland

Nearly three quarters of Finland is forestland, making it one of the most forested countries in the world, let alone Europe. As a result, wood plays a large part in Finnish culture. Stora Enso, one of the world’s leading paper and packaging manufacturers is Finnish and more than 20% of the country’s exports are from wood and wood products. Coupled with a strong focus generating much of its energy from renewables, energy derived from wood and products made from wood is high.

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United Kingdom

In 2013, less than 10% of all energy used in the UK was generated from wood and wood products. This places it some way behind countries like Germany and Sweden, in part owing to a lack of infrastructure for providing heating derived from wood and wood biomass.

This could change if the government continues to back technologies equally in initiatives like the Renewable Heat Incentive (RHI). Available to homeowners, landlords and commercial customers, RHI provides incentives for installing generators of renewable heat such as wood pellet boilers.

To reach climate goals, the then Department of Energy and Climate Change noted that both biomass-driven electricity generation and heating should continue to increase in the UK. And with the upgrade of Drax and Lynemouth power stations from coal to compressed wood pellets, there are positive signs the UK can catch up to the European biomass average. In doing so, renewable biomass electricity generation can also help increase wind and solar power generation in the UK, and help create a more sustainable energy future.

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