UK startup eyes abandoned mine shafts for energy storage

Disused mine shafts around the UK could soon be used as giant gravity batteries, capable of reacting to grid demands in under a second.

Startup Gravitricity, which has just received a £650,000 grant from Innovate UK, plans to use abandoned shafts to house massive weights. When energy is plentiful, the weights will be winched towards the surface, in much the same way that water is driven uphill in pumped hydro storage. However, unlike pumped hydro, the system should be able to respond to fluctuations in demand almost instantly.

“As we rely more and more on renewable energy, there is an increasing need to find ways to store that energy – so we can produce quick bursts of power exactly when it is needed,” said Gravitricity managing director Charlie Blair.

“So far there is a lot of focus on batteries, but our idea is quite different. Gravitricity uses a heavy weight – up to 2000 tonnes – suspended in a deep shaft by cables attached to winches. When there is excess electricity, for example on a windy day, the weight is winched to the top of the shaft ready to generate power.”

Charlie Blair

“This weight can then be released when required – in less than a second – and the winches become generators, producing either a large burst of electricity quickly, or releasing it more slowly depending on what is needed.”

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According to Blair, the system is capable of operating for decades without degradation and could have a lifespan of around 50 years. Models from 1 to 20MW will be offered, with a part-scale demonstrator planned for later this year.

Gravitricity is currently seeking to partner with investors, including those who can bring mining experience to the team. The company is also examining a number of disused mine shafts – both in the UK and South Africa – and hopes to have a full-scale working prototype up and running by 2020.


Winds of change: Seven key statistics of Europe’s booming offshore wind industry

A new report released on Tuesday (6 February) by WindEurope highlights a record year for Europe and UK offshore wind projects. Diving into the data, EURACTIV’s media partner edie brings you seven surprising statistics, from the continent’s booming offshore industry.

Offshore wind is quickly becoming a mainstream energy source for nations, with installation costs tumbling at record rates. The UK enjoyed its “greenest year ever” in 2017, and offshore projects played a big part in that.

Across Europe, the trajectory also looks promising, with WindEurope’s latest report outlining huge growth in the market.

Wind Europe’s chief executive Giles Dickson said: “Offshore wind is now a mainstream part of the power system. And the costs have fallen rapidly. Investing in offshore wind today costs no more than in conventional power generation.

“It just shows Europe’s ready to embrace a much higher renewable target for 2030. 35% is easily achievable. Not least now that floating offshore wind farms are also coming on line.”

But as 2020 deadlines for European-based renewables policy close in, how do current and future trends stack up? Edie has looked through the report to bring readers seven key takeaways from Europe’s booming offshore wind industry.

1) UK the leader in offshore wind

Of the new capacity added to the grid in 2017, the UK and Germany accounted for the most, adding 1.7 GW and 1.3 GW respectively. But it is the UK that leads the charge for offshore wind projects, accounting for 53% of all net capacity brought online. In fact, 67% of all net capacity installations occurred in the North Sea.

A further 400MW deriving from UK Round 3 projects will connect to the grid in 2018. The offshore market will continue to centre around the UK, as the nation adds 3.3GW of new grid-connected capacity by 2020 – well ahead of Germany’s scheduled 2.3 GW pipeline.

2) Europe’s capacity grew by a quarter

More than 3.1GW of net capacity was connected to the grid across Europe in 2017, taking total capacity on the continent to 15.8GW. This represented an increase of 25% in just one year and was 4% higher than the previous record in 2015.

Europe now has more 4,000 offshore wind turbines operating across 11 countries. A total of 13 new windfarms were completed – including the world’s first floating offshore windfarm in Scotland. Another 11 projects are also scheduled for construction, which will add another 2.9GW. WindEurope predicts that by 2020, Europe’s offshore portfolio will hit 25GW.

3) Five countries account for nearly all projects

Despite the record growth, offshore wind across Europe is heavily concentrated within a small cluster of countries. In fact, 98% of offshore wind capacity comes from the UK, Germany, Denmark, the Netherlands and Belgium.

The UK accounts for the largest amount of installed offshore capacity across Europe at 43%, with Germany following at 34%. Despite adding no new projects in 2017, Denmark sits third with an 8% share, in front of the Netherlands (7%) and Belgium (6%).

4) Investment is down, but that might not be a bad thing

In 2017, investment into new European offshore projects fell by almost 60%, with final investment decisions (FIDs) granted to a further 2.5GW of capacity. These investments total just €7.5bn, but WindEurope notes that this reflects the falling costs of the technology rather than a lack of appetite.

In fact, new investments were still able to access feed-in-tariffs in 2016, which reduced costs further. Auctions held over the last two years should create FIDs totalling €9bn in 2018. As for refinancing, investment hit record levels of €4.6bn, bringing total sector investment to more than €12bn.

5) France set to become a world leader

According to the report, France officially inaugurated its first offshore wind turbine in 2017 – creating a total of 2MW of net installed capacity. However, with President Emmanuel Macron pledging to increase the nation’s renewable energy portfolio, rapid acceleration is expected. WindEurope predicted that France will become the second largest market by 2021.

Projects off the French coast are expected to expand and accelerate from 2020, potentially turning the nation into Europe’s fourth-largest offshore wind generator by 2030. Around 4.3GW of net capacity is pipelined over that decade.

6) Siemens Gamesa has control in Europe

In regards to manufacturing and construction, Siemens Gamesa Renewable Energy currently accounts for 51% of new installed capacity. MHI Vestas is some way off, with a 24.7% share of the market. While more manufacturers entered the market in 2017, the two companies still accounted for more than three-quarters of installed capacity.

Regarding connection and ownership, Ørsted – formerly DONG Energy – connected the most megawatts to the grid in 2017, gaining a 19% markets share of ownership in the process.

7) The market needs policy clarity

WindEurope’s report warns that the number of grid-connected projects will fall around 2020, due to European Member States meeting National Renewable Energy Action Plans under the Renewable Energy Directive.

In the short-term, Belgium and Denmark are expected to add between 1 to 1.3GW of capacity each, while the Netherlands has pledged to install 1GW a year between 2023 and 2030; already, the Borselle III and IV and Hollandse Kust Zuid I, II, III & IV windfarms are scheduled for connection by 2022.

The UK’s next Contract for Difference Auction also takes place in 2019, with £557m in funding set aside for “less established” renewables, including offshore wind. Despite numerous national pledges, the European Union will likely have to re-establish renewable energy targets to spur on growth in the sector.

COMMENT: Get smart – there’s an energy revolution going on, says Pinsent Masons

The issues facing Scotland’s ­cities as they try to keep pace with the smart energy revolution and harness innovations in renewable ­energy takes centre stage on 20 February at ­Scottish Renewables’ Low-Carbon Cities Conference in Edinburgh.

Sponsored by Pinsent Masons, the ­conference will feature industry leaders, local and national politicians and major stakeholders, who will discuss how ­Scotland can make best use of its formidable natural resources and continue the transition to a low-carbon economy.

Certainly, there is no lack of ambition, as laid out in December in the Scottish ­Government’s strategy A 2050 Vision for Energy, which set two new targets – firstly, the equivalent of 50 per cent of the energy for Scotland’s heat, transport and electricity consumption to be supplied from renewable sources, and secondly an increase by 30 per cent in the productivity of energy use across the Scottish economy.

Whilst the focus on renewable energy generation continues to be key to the ­energy strategy, it is clear that energy efficiency measures, the management of energy consumption and the promotion of storage and system flexibility and further innovation are priority focus areas.

The ambitious framework set out in the energy strategy sends an important ­message to business regarding the potential for investment in low-carbon projects located in Scotland. This is particularly clear in relation to the need to see real progress in the decarbonisation of heat.

Innovation is also required for the roll-out of electric or other low-emission forms of transport and economic opportunities will emerge from the necessary changes that Scotland’s energy system will create in order to deliver this strategy and a more localised energy system that integrates smart technologies.

This all chimes with the findings in a ­Pinsent Masons commissioned survey, Smart Energy – Hungry for Change, which amongst other things looked at the ­evolution of mobile technology and the development of smart energy and ­infrastructure projects on a global scale.

Cities are a logical starting point for smart energy projects and Scotland will be following the example of the likes of Amsterdam, Barcelona and Oslo, which are already encouraging the adoption of smart energy technologies through the roll-out of smart city initiatives.

Turning smart city concepts into reality, however, is never straightforward, and according to our survey findings, ­utilities companies and investors are somewhat split on the best way forward. Utilities – which bear ultimate responsibility for delivering the smart energy portion of such initiatives – are clear about the ­support mechanisms needed for these projects to succeed, with 44 per cent believing legislative support is most crucial and 36 per cent favouring more financial support.

Investors, not surprisingly, have a different perspective – financial support is seen as the most important mechanism by 50 per cent of respondents, with organisational assistance favoured by 28 per cent.

One area where the smart energy industry has been given a leg-up is in local government policy. In the UK for example, Bristol and Peterborough have for some years been ­promoting smart technologies, including electric vehicles and renewable energy.

The smart cities drive is helping to change the focus of the smart energy market as local authorities open up public sector assets, such as data, and enable the private sector to innovate using those assets. Some local authorities are also providing public sector money to support private sector investment in smart cities and smart energy technologies, and this gives businesses comfort that they are not alone in taking on the risks involved in pushing forward with innovation and developing and commercialising new technologies.

Kate Turner, legal director and specialist in energy projects at legal firm Pinsent Masons

UK 'needs' FiT solution

Renewables industry groups, including RenewableUK (R-UK) have called on the UK government to provide clarity on the future of the feed-in tariff (FiT), which is currently set to close in 2019.

Uncertainty over the Fit, which supports household, farm and small business-scale renewable energy installations, has caused investment in the sector to slump, the groups said.

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They have written a joint letter to the Secretary of State for Business, Energy and Industrial Strategy Greg Clark on the issue.

“We would stress that without a viable route to a market, the benefits that small-scale low-carbon energy projects can deliver to the UK risk being lost,” the letter said.

The groups added that a consultation on what will happen after 2019 is now a year overdue.

“Investor confidence in the sector is waning, with developers increasingly looking to invest elsewhere,” the letter added.

The government was asked to urgently consult on the future of the FiT, as well as operational issues.

Other signatories to the letter are Community Energy Scotland, Country Land & Business Association, EnergyUK, National Farmers Union, Scotland Regen, Scottish Land and Estates, Scottish Renewables, Solar Trade Association and The Anaerobic Digestion & Bioresources Association.

Image: Free Images/Christian Wagner