Advocates claim enough geothermal energy in abandoned coal mines to heat 180m homes. The weed-lined disused road beside Lanchester Wines’ ageing warehouse on a north-east England industrial estate could not be more low key. But beneath the roadway’s many manhole covers are shafts which descend 200m into what could be the UK’s most widespread unused energy source – minewater. Lanchester Wines’ facility in Gateshead has by far the UK’s biggest commercial minewater heating scheme. It supplies all the warehouse’s needs, keeping millions of bottles of wine temperate, and also heats a neighbouring distribution depot. Advocates of using minewater for heating regard it as having particularly significant potential after the UK set the ambitious goal earlier this year of net zero greenhouse gas emissions by 2050. A quarter of all UK homes and businesses, some 9m buildings, and most of its largest cities outside London sit on former coalfields. Coal mining, which employed 1.25m people at its peak, powered the British economy for well over a century but the last deep mine closed in 2015. One of its underground legacies is the warrens of galleries through which run an estimated 2bn cubic metres of water, heated by surrounding rocks to 12-16 degrees Celsius. At present, minewater is a problem. Often high in iron and pollutants and potentially a threat to drinking water and rivers, its management by the publicly funded Coal Authority cost £18m last year. Yet Lisa Pinney, the authority’s chief executive, said minewater “could be a real contribution to zero carbon”. Opportunities she cited included horticulture, new housing and leisure schemes. According to Coal Authority data, heating currently accounts for 45 per cent of the country’s energy use and 32 per cent of its emissions. Meeting the government’s net zero carbon emissions target will require slashing fossil fuel use. Three extraction shafts outside the warehouse raise 39 litres of minewater a second to the surface using an open loop water source heat pump system. The minewater travels by pipe around the plant room into a heat exchanger. Here, the minewater heat boils liquid ammonia, concentrating the ammonia’s heat at 50 degrees C. This heat is then used to warm water which circulates around the factory’s heating system. Meanwhile the minewater, above ground for only two minutes, is sent back underground to warm up again. Now the 60-year-old Gateshead warehouse has a 2.4MW system yielding 6KW of heat for each kilowatt of electricity used. Its installation has brought the company its first payment, of £117,000 payment, under the government’s renewable heat incentive scheme. The company’s other nearby warehouse, which has hit an even better minewater supply yielding 67 litres a second, will within weeks start operating its own heating scheme. Mr Black expects payback on the £3.5m investment, part of £8m spent on renewable energy to make the company carbon neutral, within seven years. In Bridgend, in south Wales, the local authority is working with scientists to develop a minewater heating network for a local community. And in Durham the county council has invited tenders for heating a leisure centre swimming pool using minewater. Mike Stephenson, the BGS’s chief scientist, said the Glasgow studies were focusing on “de-risking” minewater heat use and that the research should be sufficiently advanced to enable investment decisions in two years.  “The wonderful irony here is we used coal to carbonise the economy,” he said. “Now we are going to use the coal mines that exist to decarbonise.”

Financial Times »

Engineers in Stirling are getting ready to open the UK’s first low-carbon energy hub which uses waste water. Scottish Water aims to heat several public buildings, including a school, a leisure centre and a stadium, through a mixture of cutting-edge technologies, including heat pumps, at its sewage works at Forthside. Their £6 million scheme, which has financial backing from Stirling Council and the Scottish Government, was visited by First Minister Nicola Sturgeon yesterday ahead of its switch-on next month. The new energy hub consists of a conventional natural gas combined heat and power (CHP) engine, heat from a waste water heat pump system, thermal stores and back-up gas boilers for the district heating network. The CHP engine generates heat for the public buildings and electricity for the sewage plant and the waste water heat pumps. The heat from waste water technology, provided by SHARC Energy Systems, uses a heat recovery unit to separate liquid and solid waste, which is returned to the treatment process. A heat exchanger transfers the heat from the waste water to the clean water using a closed loop system. A heat pump increases the temperature of the water, which is then delivered to the district heat network. Electric heat pumps – essentially reverse fridges – are being developed on an industrial scale across the planet. In Clydebank, local authorities hope to use pumps to capitalise on the relative warmth of the local river to heat a new neighbourhood. Scotland has Europe’s worst record on renewable heat.

Herald »

Using hydrogen to heat homes and power vehicles will play a vital part in Britain’s efforts to meet stringent climate targets and can’t be dismissed as an expensive pipe dream. That’s the conclusion of National Grid Plc’s network service operator in its annual Future Energy Scenarios outlook. It anticipates 11 million homes will be heated by hydrogen by 2050, which is half of the number currently using natural gas. To get to a world that limits global warming to acceptable levels, hydrogen will be in widespread use across heat, transport and industrial processes, National Grid ESO said in the report. Policy makers should act immediately to maintain hope of hitting the government’s net-zero carbon emissions target by 2050, the network operator said, urging measures on a “significantly greater scale” than it had suggested a year ago.

Bloomberg »

DANISH-style district heating projects could cut fuel poverty in rural communities, according to a joint paper by gas firm Calor, think tank Common Weal and the Energy Poverty Research Initiative. The cost of rural district heating is not substantially higher than urban district heating schemes. This is because, while the distances are greater, the necessary pipework is easier to install because access is easier.However, this solution may only work for 60% of properties and those that cannot be connected could use biogas boilers in conjunction with building-mounted solar generators, the research found. The conclusion is based on research carried out with Glasgow Caledonian University and comes decades after Denmark took steps to create its large-scale networks, which collect “waste” heat from factories and transport systems and redistribute this. They also take in energy from conventional power stations and renewables. More than 90% of rural residents who are income poor are also fuel poor, according to research. This is far higher than in towns and cities and the problem is linked to poor physical and mental health and lower education attainment. Some campaigners summarise the situation for struggling households as a “heat or eat” choice.

The National  »

Really disruptive technologies tend to be fairly rare in the renewable energy market. However, the heat batteries developed by Sunamp, which specialises in this area, look to be capable of being more disruptive than most of the innovations one sees in this space. Andrew Bissell, the CEO of Sunamp, claims that his products are highly likely to make conventional hot water cylinders obsolete in a relatively short space of time. The technology is now in its third iteration and is barely a third of the size of a typical hot water cylinder, such as households use for hot water. However, the company is currently prototyping much larger versions capable of scaling up to provide the heating needs of commercial companies from palette-sized to container-scale. In 2013, the Department of Energy and Climate Change gave Sunamp a contract to put the thermal storage system, alongside off-peak electricity and air-source heat pumps, into seven homes as a proof of concept trial. That was very successful heating the homes at half the cost of natural gas. The Sunamp put heat batteries into 650 homes. These were in two housing associations, East Lothian Housing and Castle Rock Edinvar.

Herald  »

Research from Northern Gas Networks and ITM Power concludes large scale power-to-gas energy storage could integrate with current gas networks. Ambitious plans to harness hydrogen’s potential as a form of energy storage and then inject the resulting green gas into the existing gas network could be delivered at scale, according to a major new government-backed feasibility study. Northern Gas Networks (NGN) and hydrogen technology specialist ITM Power announced this week that they have completed a collaborative desktop study, funded by the Department for Business, Energy and Industrial Strategy to explore the potential for large scale power to gas installations. The Power-to-Gas study examined potential deployment of large-scale storage capacity of 50 MW and above within the boundaries of NGN’s distribution network. It concluded that after accounting for seasonal variations in gas demand and the amount of hydrogen that would be able to be produced and blended with natural gas, a large area of the existing NGN grid could support power-to-gas.

Business Green »

Scientists are finalising plans to exploit the vast reservoir of warm water that fills a labyrinth of disused mines and porous rock layers underneath Glasgow. They believe this subterranean store of naturally heated water could be used to warm homes in the city. If the system proves successful, such water could then be exploited in other cities and towns across Britain, they say. The £9m project will initially involve drilling narrow boreholes filled with instruments to survey temperature, seismic activity, water flow, acidity and other variables to establish the state of the water in the rocks below the city. The aim will be to establish whether this warm water can be extracted for long periods to heat Glaswegian homes. Drilling of the first test boreholes – at sites yet to be selected – is the first part of an initiative by the BGS: the creation of several UK geo-energy observatories. Where other observatories look up to the sky, these will monitor conditions underground, say scientists. One test system has been selected for Scotland: the Glasgow Geothermal Energy Research Field Site. A second has been proposed for Cheshire – where scientists want to study rock conditions to assess the possibility of using underground vaults as storage for heated water. Heating of homes is set to become a crucial issue, researchers have warned. The UK is on target to decarbonise electricity generation as a result of the growing numbers of renewable power plants. However, the nation is still heavily reliant on North Sea and imported natural gas to heat its homes. Combustion of these fossil fuels forms a substantial part of the carbon dioxide emissions which the UK has pledged to reduce to help limit glob al warming.

Observer »