Tag: biomass energy

4 amazing uses of bioenergy

5 April 2017

Sustainable bioenergy
Large modern aircraft view of the huge engine and chassis, the light of the sun

Bioenergy is the world’s largest renewable energy source, providing 10% of the world’s primary supply. But more than just being a plentiful energy source, it can and should be a sustainable one. And because of this, it’s also a focus for innovation.

Biomass currently powers 4.8% of Great Britain’s electricity through its use at Drax Power Station and smaller power plants, but this isn’t the only way bioenergy is being used. Around the world people are looking into how it can be used in new and exciting ways.

algal blooms, green surf beach on the lakePowering self-sufficient robots 

What type of bioenergy?

Algae and microscopic animals

How’s it being used?

To power two aquatic robots with mouths, stomachs and an animal-type metabolism. Designed at the University of Bristol, the 30cm Row-Bot is modelled on the water boatman insect. The other, which is smaller, closer resembles a tadpole, and moves with the help of its tail.

Both are powered by microbial fuel cells – fuel cells that use the activity of bacteria to generate electricity – developed at the University of the West of England in Bristol. As they swim, the robots swallow water containing algae and microscopic animals, which is then used by their fuel cell ‘stomachs’ to generate electricity and recharge the robots’ batteries. Once recharged, they row or swim to a new location to look for another mouthful.

Is there a future?

It’s hoped that within five years the Row-Bot will be used to help clean up oil spills and pollutants such as harmful algal bloom. There are plans to reduce the tadpole bot to 0.1mm so that huge shoals of them can be dispatched to work together to tackle outbreaks of pollutants.

multi-coloured water ketttlesPurifying water

What’s used?

Human waste

How’s it being used?

The Omni Processor, a low cost waste treatment plant funded by the Bill and Melinda Gates Foundation, does something incredible: it turns sewage into fresh water and electricity.

It does this by heating human waste to produce water vapour, which is then condensed to form water. This water is passed through a purification system, making it safe for human consumption. Best of all, it does this while powering itself.

The solid sludge left over by the evaporated sewage is siphoned off and burnt in a steam engine to produce enough electricity to process the next batch of waste.

Is there a future?

The first Omni Processor was manufactured by Janicki Bioenergy in 2013 and has been operating in Dakar, Senegal, since May 2015. A second processor, which doubles the capacity of the first, is currently operating in Sedro-Woolley, Washington, US and is expected to be shipped to West Africa during 2017.

Closer to home and Drax Power Station, a similar project is already underway. Northumbrian Water was the first in the UK to use its sludge to produce renewable power, but unlike the Omni Processor, it uses anaerobic digestion to capture the methane and carbon dioxide released by bacteria in sludge to drive its gas turbines and generate power. Any excess gas generated is delivered back to the grid, resulting in a total saving in the utility company’s carbon footprint of around 20% and also multi-millions of pounds of savings in operating costs.

Jet plane leaves contrail in a sunset beautiful sky, copy space for textFlying across the Atlantic

What’s used?

Tobacco

How’s it being used?

Most tobacco is grown with a few factors in mind – taste and nicotine content being the most important. But two of the 80 acres of tobacco grown at Briar View Farms in Callands, Virginia, US, are used to grow tobacco of a very different sort. This tobacco can power aeroplanes.

US biofuel company Tyton BioEnergy Systems is experimenting with varieties of tobacco dropped decades ago by traditional growers because of poor flavour or low nicotine content. The low-nicotine varieties need little maintenance, are inexpensive to grow and flourish where other crops would fail.

The company is turning this tobacco into sustainable biofuel and last year filed a patent for converting oil extracted from plant biomass into jet fuel.

Is there a future?

In the hope of creating a promising source of renewable fuel, scientists are pioneering selective breeding techniques and genetic engineering to increase tobacco’s sugar and seed oil content.

In 2013, the US Department of Energy gave a $4.8m grant to the Lawrence Berkeley National Laboratory, in partnership with UC Berkeley and the University of Kentucky, to research the potential of tobacco as a biofuel.

Fukushima Japan

Powering repopulation of a disaster zone

What’s used?

Wood exposed to radiation by the Fukushima nuclear meltdowns

How’s it being used?

Last year it was announced that German energy company Entrade Energiesysteme AG, will set up biomass power generators in the Fukushima prefecture that will generate electricity using the lightly irradiated wood of the area.

It’s hoped they will help Japan’s attempts to repopulate the region following the 2011 earthquake, tsunami and nuclear accident. Entrade says its plants can reduce the mass of lightly irradiated wood waste by 99.5%, which could help Japanese authorities reduce the amount of contaminated material while at the same time generating sustainable energy.

Is there a future?

The prefecture aims to generate all its power from renewable energy by 2040 through a mix of bioenergy and solar power.

Sustainability, certified

24 March 2017

Sustainable bioenergy
Drax Morehouse woodchip truck

Of all the changes to Drax Power Station over the last decade, perhaps the biggest is one you can’t see. Since converting three of its six generating units from coal to run primarily on compressed wood pellets, Drax has reduced those units’ greenhouse gas (GHG) emissions by over 80%.

And while this is a huge improvement, it would mean nothing if the biomass with which those reductions are achieved isn’t sustainably sourced.

For this reason, Drax works with internationally-recognised certification programmes that ensure suppliers manage their forests according to environmental, social and economic criteria.

Thanks to these certification programmes, Drax can be confident it is not only reducing GHG emissions, but supporting responsible forestry from wherever wood fibre is sourced.

Sustainability certifications

The compressed wood pellets used at Drax Power Station come from various locations around the world, so Drax relies on a number of different forest certification programmes, the three main ones being the Sustainable Forest Initiative (SFI), Forest Stewardship Council® (FSC®)1 and the Programme for the Endorsement of Forest Certification (PEFC).

The programmes share a common goal of demonstrating responsible forest management, but adoption rates vary by region. European landowners and regulators are most familiar with the FSC and national PEFC standards, while North American landowners generally prefer SFI and American Tree Farm System (also members of the PEFC family). In instances in which Drax sources wood pellets carrying these certifications, or in instances in which Drax purchase pellets sourced from certified forests, these certifications offer an additional degree of assurance that the pellets are sustainable.

Over 50% of the pellets used at Drax Power Station come from the southern USA, where SFI and American Tree Farm System are the most widely implemented certification programmes. Overall adoption levels in this region are relatively modest. However, the SFI offers an additional level of certification that can be implemented by wood-procuring entities, such as sawmills, pulp mills and pellet mills.

This programme is referred to as SFI Fiber Sourcing, and to obtain it, participants must demonstrate that the raw material in their supply chains come from legal and responsible sources. These sources may or may not include certified forests. The programme also includes requirements related to biodiversity, water quality, landowner outreach and use of forest management and harvesting professionals. Together, these certification systems have long contributed to the improvement of forest management practices in a region that provides Drax with a significant proportion of its pellets.

And since the SFI and ATFS programmes are endorsed by PEFC, North American suppliers have a pathway for their region’s sustainable forest management practices to be recognised by European stakeholders.

These certification programmes have been in use for many years. But with recent growth in the market for wood pellets, a new certification system has emerged to deal specifically with woody biomass.

Trees locked up in a bundle

New kid on the block

The Sustainable Biomass Program (SBP) was set up in 2013 as a certification system to provide assurance that woody biomass is sourced from legal and sustainable sources. But rather than replacing any previous forest certification programmes, it builds on them.

For example, SBP recognises the evidence of sustainable forest management practices gathered under these other programmes. However, the PEFC, SFI and FSC programmes do not include requirements for reporting GHG emissions, a critical gap for biomass generators as they are obligated to report these emissions to European regulators. SBP fills this gap by creating a framework for suppliers to report their emissions to the generators that purchase their pellets.

When a new entity, such as a wood pellet manufacturer, first seeks certification under SBP, that entity is required to assess its supply base.

Feedstock which has already been certified by another established certification programme (SFI, FSC®, PEFC or PEFC approved schemes) is considered SBP-compliant.

All other feedstock must be evaluated against SBP criteria, and the wood pellet manufacturer must carry out a risk assessment to identify the risk of compliance against each of the 38 SBP indicators.

If during the process a specific risk is identified, for example to the forest ecosystem, the wood pellet manufacturer must put in place mitigation measures to manage the risk, such that it can be considered to be effectively controlled or excluded.

These assessments are audited by independent, third party certification bodies and scrutinised by an independent technical committee.

In conducting the risk assessment, the wood pellet manufacturer must consult with a range of stakeholders and provide a public summary of the assessment for transparency purposes.

Sustainable energy for the UK

Counting major energy companies including DONG Energy, E.ON and Drax as members, the SBP has quickly become an authoritative voice in the industry. At the end of 2016, the SBP had 74 certificate holders across 14 countries – including Drax’s pellet manufacturing arm, Drax Biomass, in Mississippi and Louisiana.

It’s a positive step towards providing the right level of certification for woody biomass, and together with the existing forestry certifications it provides Drax with the assurance that it is powering the UK using biomass from legal and sustainable sources.

Like the fast-reducing carbon dioxide emissions of Britain’s power generation sector, it’s a change you can’t see, but one that is making a big difference.

Read the Drax principles for sustainable sourcing.

1 Drax Power Ltd FSC License Code: FSC® – C119787

More power per pound

23 March 2017

Sustainable bioenergy

As the country moves towards a lower carbon future, each renewable power generation technology has its place. Wind, solar, hydro and wave can take advantage of the weather to provide plentiful power – when conditions are right.

Reliable, affordable, renewable power

But people need electricity instantly – not just when it’s a windy night or a sunny day. So, until a time when storage can provide enough affordable capacity to store and supply the grid with power from ample solar and wind farms, the country has to rely, in part, on thermal generation like gas, coal and biomass. Reliable and available on demand, yes. But renewable, low carbon and affordable too? It can be.

A year ago, a report by economic consultancy NERA and researchers at Imperial College London highlighted how a balanced mix of renewable technologies could save bill payers more than £2bn. Now, publicly available Ofgem data on which its newly published Renewables Obligation Annual Report 2015-16 is based reinforces the case for government to continue to support coal-to-biomass unit conversions within that technology mix. Why? Because out of all renewables deployed at large scale, biomass presents the most value for money – less public funding is required for more power produced.

Renewable costs compared

Drax Power Station’s biomass upgrades were the largest recipient of Renewable Obligation (RO) support during the period 2015-16. The transformation from coal to compressed wood pellets has made Drax the largest generator of renewable electricity in the country. And by a significant margin. Drax Power Station produced more than five times the renewable power than the next biggest project supported under the RO – the London Array.

Dr Iain Staffell, lecturer in Sustainable Energy at the Centre for Environmental Policy, Imperial College London, and author of Electric Insights, who has analysed the Ofgem data commented:

“Based on Ofgem’s Renewables Obligation database, the average support that Drax Power Station received was £43.05 per MWh generated. This compares to £88.70 per MWh from the other nine largest projects.”

“Biomass receives half the support of the UK’s other large renewable projects, which are all offshore wind. The average support received across all renewable generators in the RO scheme – which includes much smaller projects and all types of technology – is £58 per MWh. That is around £15 per MWh more than the support received by Drax.”

Ending the age of coal

Drax Group isn’t arguing for limitless support for coal-to-biomass conversions. And Drax Power Station, being the biggest, most modern and efficient of power stations built in the age of coal, is a special case. But if the RO did exist just to support lots of biomass conversions like Drax but no other renewable technologies, then in just one year, between 2015-16, £1bn of costs saving could have been made for the public purse.

Drax Power Station may be the biggest-single site recipient of support under the RO – but it does supply more low carbon power into the National Grid than any other company supported by Renewable Obligation Certificates (ROCs). In fact, 65% of the electricity generated at its Selby, North Yorkshire site, is now renewable. That’s 16% of the entire country’s renewable power – enough to power four million households.

Thanks to the support provided to Drax by previous governments, the current administration has a comparatively cost effective way to help the power sector move towards a lower carbon future. Biomass electricity generated at Drax Power Station has a carbon footprint that is at least 80% less than coal power – supply chain included. Drax Group stands ready to do more – which is why research and development continues apace at the power plant. R&D that the company hopes will result in ever more affordable ways to upgrade its remaining three coal units to sustainably-sourced biomass, before coal’s 2025 deadline.

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.

Forests are more powerful than you think – here’s why

21 March 2017

Sustainable bioenergy

Almost one third of the earth’s land mass is covered by forests. That’s an area of around 4 billion hectares, or roughly four times the size of the US.

In addition to being a prominent feature across the global landscape, forests also play a significant role in how we live. They make the air cleaner in cities and absorb carbon from the atmosphere. They provide bio-diversity and habits for wildlife. They also provide essential forest products such as paper, building materials and wood pellets for energy.

To celebrate the UN’s International Day of Forests, we’re looking at some of the reasons why forests and wood fuel are more powerful than you might think.

They’re a major source of renewable energyFamily at home using renewable energy.

Nearly half of the world’s renewable energy comes from forests in the form of wood fuel. Roughly 2.4 billion people around the world use it for things like cooking, heating and generating electricity. In fact, about 50% of the total global wood production is currently used for these purposes.

However, it is critical that this resource is managed sustainably and responsibly. One of the key aims of the International Day of Forests is to encourage people to utilise their local forest resources sustainably to ensure it endures for future generations.

They can revitalise economiesA truck unloading.

Because wood fuel is such a widely used energy source, it also supports a healthy, vibrant industry. Roughly 900 million people work in the wood energy sector globally.

More than that, rural economies built on wood energy can be revitalised by modernisation, which can then stimulate local business. Investment can help finance better forest management, which in turn leads to forest growth, improvements in sustainability standards and in some cases, increased employment.

They can help mitigate climate changeYoung sapling forest.

The world’s forests have an energy content about 10 times that of the global annual primary energy consumption, which makes it a hugely useful resource in helping meet energy demand in a sustainable and renewable way.

When wood is used as fuel it releases carbon dioxide (CO2). However, if this fuel is drawn from a responsibly managed forest or sustainable system of growing forests this carbon is offset by new tree plantings. The only emissions produced therefore are the ones involved in transporting the wood itself. The US Food and Agriculture Organization predict that by 2030 forestry mitigation with the help of carbon pricing could contribute to reductions of 0.2 to 13.8 Gigatonnes (Gt) CO2 a year.

Chief Executive comments on full year results

Dorothy Thompson, (2005-2017 Chief Executive, Drax Group)

16 February 2017

Investors

We are playing a vital role in helping change the way energy is generated, supplied and used as the UK moves to a low carbon future.

With the right conditions, we can do even more, converting further units to run on compressed wood pellets. This is the fastest and most reliable way to support the UK’s decarbonisation targets, whilst minimising the cost to households and businesses.

In a challenging commodity environment Drax has delivered a good operational performance with 65% renewable power generation.

 

The acquisition of Opus Energy and rapid response open cycle gas turbine projects are an important step in delivering our strategy, diversifying our earnings base and contributing to stronger, long-term financial performance across the markets in which we operate.

Related documents:

A positive negative

18 January 2017

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

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

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

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

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

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

Capturing carbon

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

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

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

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

Two technologies, working as one

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

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

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

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

Morehouse BioEnergy pellet plant

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

Positive support for negative emissions

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

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

Drax research and development

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

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

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

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

Building a 21st century port

16 November 2016

Sustainable bioenergy

In its long history, the Port of Liverpool has dealt with a number of industries. It’s a port characterised by its ability to adapt to the needs of the time. In 1715 it emerged as one of the world’s first ever wet docks. In the 18th century it was used as a hub for the slave trade.

When slavery was abolished in the early 19th century, Liverpool switched to bringing in the goods of the thriving Empire, such as cotton. When goods like cotton dried up, it switched to the fuel of the Industrial Revolution: coal.

Now as the world (and the UK government) moves away from fuels like coal and towards lower-carbon and renewable resources, the Port of Liverpool needed to adapt once again.

Gary Hodgson, Chief Operating Officer at Peel Ports, explains: “About three years ago everyone was asking, ‘What happens after coal?’”

Biomass silos at the Port of Liverpool

What happens after coal?

Peel Ports is one of the biggest operators of Liverpool’s shipping infrastructure, including Liverpool Port. Seeing that the future of coal was finite, it recognised there was a need for a port that could bring in alternative, renewable fuels.

At the same time Drax was looking for a logistics partner to facilitate the importing of compressed wood pellets. Since 2009 Drax Power Station had begun a process of upgrading its coal-fired boilers to run on sustainable biomass, sourced from huge, well-established working forests. More than this, it had plans to set up its own pellet manufacturing plants in the US South and needed to import large quantities of wood pellets.

The relationship with Peel Ports and Liverpool was obvious. This began a £100 million investment that helped transform the region’s port-station transport infrastructure.

“It’s about working in partnerships with companies,” says Hodgson. “Working this way helps develop solutions that really work.”

The central element of the partnership between Drax and Peel Ports was a radical redesigning of the technical infrastructure. Not only do compressed wood pellets have fundamentally different physical properties to other fuels like coal, they are more combustible and need to be handled safely.

For the three-million-tonne-capacity facility that Peel Ports and Drax wanted to build, innovative supply chain solutions had to be developed.

A tool used to transfer compressed biomass pellets

Shifting biomass in bulk

The first challenge was getting the high-density pellets off giant ships. For this, Peel and Drax designed a solution that uses an Archimedean screw – a long tube with a spiral winding up the inside that allows liquids, or materials that can behave like a liquid (like wood pellets), to defy gravity and travel upwards.

At the top of the screw, the pellets are emptied onto a conveyor belt and carried to one of three purpose-built silos tailored to safely storing thousands of tonnes of biomass.

Here the pellets wait until another conveyor belt deposits them onto specially-design biomass trains where they are transported across the peaks of the Pennines to Drax Power Station near Selby in North Yorkshire.

Each step at the port is automated, designed with supreme efficiency in mind by a team of Drax and Peel Port engineers. End-to-end, port to power station, the whole process can take as little as 12 hours.

Drax biomass ship in the Port of Liverpool

A new chapter for the north

In the varied history of the Port of Liverpool the new facility is another chapter, one that is helping transform the logistics infrastructure and the economic growth of the North West.

Now open and operational, the facility directly employs 50 people – around 500 additional contractors have worked on the project during its construction and development. More than that, it’s an investment in the country’s energy future. It secures a fourth port for Drax –  three others are on the east coast – helping with security of supply.

“We made this investment because we recognised this as the future of the energy mix of the country,” Hodgson explain. “We can’t just rely on one form of power – there has to be an energy mix and we see biomass as a key part of that.”

The cleanest year in Britain’s electricity

14 November 2016

Power generation
Cleanest year in Britain's electricity history

Amid the political upheaval that is characterising 2016 you may have missed the quiet victory of the UK’s low-carbon energy sector: for the first time ever, the third quarter (Q3) of 2016 saw more than 50% of the Britain’s power come from low-carbon energy sources. Five years ago, low-carbon sources made up just over a quarter.

This doesn’t necessarily mean that renewable energy sources made up the full 50% – in fact, nuclear made up a considerable chunk – but it hints at the big changes we’re seeing in the way the country is sourcing its power.

For one, it’s a further sign of coal’s diminishing life. During the period July to September 2012 coal supplied 38% of Britain’s electricity – during this year’s Q3 it supplied just 3%. As a result, per-unit carbon emissions from electricity consumption are at their lowest levels ever. The Carbon Price Floor – also known as the carbon tax and designed to assist energy companies like Drax invest in renewable and lower carbon generation – has played a big role in reducing coal’s contribution.

The findings come from Electric Insights, an independent report produced by researchers from Imperial College London and commissioned by Drax, that looks at the UK’s publicly available electricity data and aims to inform the debate on Britain’s electricity system.

Beyond the continued decline of coal, it shows there’s a growing diversity in low-carbon energy sources fuelling the country and that there’s a positive outlook for a cleaner electricity future.

Here we look at those low-carbon sources and how their use has changed over the last five years.

Nuclear produces 26% of Britain's power (Q3, 2016)

Nuclear

At 26% of the total, nuclear made up the largest proportion of low-carbon power generation across Q3 2016.

That was good news for the sector, which went through a turbulent summer after plans for the Hinkley Point C reactor were momentarily threatened following the dissolution of the Department for Energy and Climate Change (DECC) after the Brexit vote.

The eventual decision to continue with Hinkley C, however, means that more baseload nuclear power, in the form of large power stations and also possibly small modular nuclear reactors (SMRs), will be coming on to the system in the coming years. They will in the main replace older nuclear power stations set to be decommissioned.

Wind produces 10% of Britain's power (Q3, 2016)

Wind

Wind power made up 10% of total low-carbon power generation between July and September, and was the largest renewable source of the quarter.

As recently as 2011, electricity generated by wind accounted for just 4% of Britain’s low carbon energy supplies – a 150% increase in just five years. This is in part due to huge offshore projects such as the 630 MW London Array in the Thames Estuary and the 576MW Gwynt y Môr situated off the coast of North Wales, which have contributed to bringing the UK’s installed capacity to around 14 GW

The UK is now the world’s sixth largest producer of wind power behind China, the USA, India, Germany and Spain.

Solar produces 5% of Britain's power (Q3, 2016)

Solar

Following wind power as the second largest renewable contributor to the country’s low-carbon energy needs was solar.

Five years ago solar’s contribution was so negligible it didn’t even chart in the Electric Insights data. Fast forward to 2016 and Britain has a total installed solar capacity of nearly 10 GW. Again, this places the country sixth in the world for capacity behind China, Germany, Japan, the USA and Italy.

Biomass produces 4% of Britain's power (Q3, 2016)

Biomass

Biomass – a unique low-carbon fuel in that it can deliver both baseload and flexible power – made up 4% of the UK’s power needs in Q3 2016. A good proportion of that came from Drax, which has over the last five years been upgrading from coal to run on compressed wood pellets.

Like solar, biomass generation didn’t even chart in 2011, but today. In fact, between July and September biomass, along with solar and wind, supplied 20% of the country’s electricity – a huge proof point for the rise of renewables. Where biomass sits apart from those two sources, however, is that it isn’t dependent on weather and even though the country has less much less biomass generation capacity than the two intermittent technologies, it produces nearly as much energy as them. This makes it an ideal baseload partner for sources that do (i.e. wind and solar) as it can be dialled up and down to meet the energy demand of the country in seconds.

In the future there’s potential to increase this biomass capacity while saving bill payers money. Three of Drax’s six generating units run on biomass, but if all were to be upgraded as they could be in less than three years – Drax plus Lynemouth power station and one or two smaller biomass power stations – could generate roughly 10% of Britain’s electricity using compressed wood pellets by the time unabated coal power stations come off the system before the end of 2025.

Hydro produces 1% of Britain's power (Q3, 2016)

Hydro

Hydropower made up just 1% of Britain’s power generation over the quarter. However, this is still up by 20% since 2011, when hydropower contributed just 0.8%. Total installed hydropower capacity is around 1.65GW.

However, studies have found the country has a potential hydropower capacity of close to double this amount, but as many of these sources are located in mountainous, rural landscape areas of natural importance, it’s doubtful whether hydropower will be deployed up to its full capabilities in the coming years.

Closing an historic year

May the 5th was an historic day in the UK – it was the first time since 1881 Britain burnt no coal to produce its electricity. It wasn’t an isolated incident, either. In the third quarter of 2016 Britain was completely coal free for nearly six days.

It’s a situation that is likely to continue in the future as low carbon energy sources – and in particular renewables – continue to grow in the country’s energy makeup. The outlook is a positive one. 2016 may have been the cleanest year in UK electricity we’ve seen so far, but it won’t be the cleanest year ever.

Explore the data in detail by visiting ElectricInsights.co.uk

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.

If you’re afraid of heights, don’t do this job

27 October 2016

Power generation
Reparing the colling tower at Drax Power Station

Be they for nuclear, coal, or biomass power, cooling towers and their colossal, tapering silhouettes are the most iconic element of the architecture of energy. Drax has 12 of them.

But a structure of that size poses a considerable maintenance challenge. For the first time since Drax’s six towers were constructed between 1967 and 1974, one of them was in need of repair.

Ladder up a Drax cooling tower

What could possibly go wrong?

No matter how well you build something, things can go wrong after more than five decades of continuous operation. Each tower is made from concrete that varies in thickness from seven inches in the middle to around 15 inches at the top and bottom. Over time, even a structure this solid can begin to weaken.

Cooling towers are reinforced with steel bars embedded within their concrete which can rust and expand, causing the concrete around it to crack – a process called spalling. Water vapour, which passes through the towers on an almost constant basis, can also migrate into poorly compacted concrete inside the tower and cause further cracks.

Before the Drax team could set about repairing the towers, they needed to know where these cracks were. Inspecting a structure that tall needed an innovative solution. It needed drones.

Surveying the damage

Drones were used to make a comprehensive, photographic record of the towers that could be inspected for signs of damage. The drones also helped produce a 3D model of the structure to visualise the tower’s defects. It was the first-of-a-kind for the company.

The drone survey found that on tower 3B there were a number of cracked concrete patches on the towers that needed repairing and maintenance was scheduled to coincide with Drax’s 2016 outages – periods during the summer months when electricity demand is lower and parts of the power station undergo routine repair work.

The next challenge was how to carry out these repairs on a structure taller than the Statue of Liberty.

A 3D model of a Drax cooling tower

To inspect the cooling tower, Drax created a 3D model with the help of CyberHawk.

Engineering at an altitude

Drax tower 3B is nearly 115 metres tall, enough to fit in the Statue of Liberty or St Paul’s Cathedral with room to spare.

How do you go about repairing a structure like this? The answer: Steeplejacks. Steeplejacks were called so because, originally, they were the people used for scaling the side of church steeples to make repairs. But a cooling tower presents a distinctly different structure that can’t necessarily be climbed up from the bottom. To scale it and make the repairs, a different approach was needed.

Drax reached out to specialist steeplejack contractors Zenith Structural Access, who build devices that allow the scaling of industrial-scale structures.

Zenith’s solution was to fix a metal frame to the top of the tower, which then lowers a walkway suspended by strong metal cables down its side. From a perch suspended from the top of tower 3B, workmen were deployed to make the repairs – more than 100 metres above ground.

Suspended in their cradles, the teams sealed the surface of each crack and then injected resin to fix the cracks in the concrete shell. Where the concrete had spalled, new specialist repair mortars were applied.

Repairs on Drax Tower 3B

Regular repairs

With the identified defects on the tower fully repaired, attention can now move on to others on site. Routine inspections using drones and binoculars have been planned to take place every three years. These will monitor the condition of all the towers and allow for future maintenance to be planned in advance.

Two more towers are already scheduled for repair in 2017’s outages. Once again, it’ll be case for engineering work at elevation.