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I think you get about a 2 MWp of solar on a hectare. But let us say we can only use a quarter of it for PV effectively i.e. large enough grid connections, access, lease conditions etc. So 0.5 MWp. 120,000 x 0.5 = 60,000 or 60 GWp which is almost as large as the total capacity of the UKs generation. Picking Leicester, as it is about halfway up England, and punching in an optimally angled, 1 MWp installation into PVGIS, it shows a December output of 37 MWh, or about 11 MWh/day. Multiply that by 6,000 to match the potential resource, that could supply 66 GWh/day. A quick look at December 2020 Grid Watch demand figures shows a mean power of 33.5 GW. The peak is 47.3 GW. I would think, before land rental and connection charges, a PV farm would cost about £500,000/MWp. So 60 GWp would cost £3bn (about a sixth of what has been spent on Hinckley Point so far). OK, so storage is needed, and a lot of it, as in December all the generation is done in 9 hours, leaving 15 hours of darkness. Looking at Grid Watch again, the mean darkness demand is 31 GW, with a peak of 42 GW. So the storage would have to be in the region of 500 GWh. If a car has 50 kWh of battery storage, a million of them will have 50 GWh. I think Tesla has already made over 2 million Model 3s, so 1 company has already used, in just one of their model range, 100 GWh of batteries (the Model 3 has a battery between 57.5 and 82 kWh, but you get my point). So battery manufacture is not really an issue in this one off case, and anyway, it would be installed in phases, so spread over a few years to match the PV installation. Now I really do not have any idea what that battery storage would cost, but the unit that Tesla fitted in South Australia cost about A$90m for 150 MWh, so a quick convert to English and that is £320,000/MWh. So 500 GWh would cost around £160bn. About the same as 8 to 10 new nuclear reactors. So the total cost, to run the UK purely from PV and storage is less than £200bn (I have added a bit to cover land rental and running costs, though there should be a 'British Management' premium) . How much as been spent on HS2, £98bn so far? December 2020 electrical usage was 24,888 GWh. If we divide £200bn by 25,000 GWh, that is £8/kWh. But that would be putting all the investment onto just 1 month. A quick look at Grid Watch again and I have calculated that December 2020 used 10% of the annual electrical production (May was the lowest at 6.8%). So that means we could calculate the electricity price at 80p/kWh, if we put all the costs into 1 year. Well that would be a bit silly, so if we amortised it at 7.5 years, then the generation, storage, and probably delivery price (as I added a few million on for that), would be 11p/kWh. About a third of what we currently pay, but that is a wholesale price, so maybe a few changes in the electricity market are needed (not as if we can't do that quickly, we did last year). Back to the land area, I used a quarter of the 120,000 hectares, so 30,000 hectares. England has a total land area of 130,310 km2 or 13,031,000 Ha. 30,000 / 13,031,000 x 100 = 0.23% I think that is known, in general terms, as (expletive deleted) all. (now I have been mixing kWh, MWh, GWh, km2, hectares, pennies, £, £bn etc, so may have made an error, if I have let us find it and put it right so we can use a definitive answer to this question). Oh, and @ProDave, I have used just England land areas, but the electrical demand includes all the colonies you are in.

Routing jigs, coil formers, knife blocks, helical milling jigs, rubber feet for drainers... I can't count the practical things we use it for, in use every day.

The different voltages are a red herring, ignore. Yeah, I tend to choose German ones if I want best quality.

There's this type too: I got my lad to print an adapter to exactly fit the Makita cordless: For accurate "edge" drilling though he'll print guides for that particular board thickness that clip over the edge.

How countries can go fossil fuel free with wind and solar superpowers South Australia is a renewable energy champion and now plans a truly fossil fuel-free grid. How did it make such a remarkable turnaround, and can the rest of the world follow suit? By Alice Klein 24 October 2023 Clever use of solar and wind energy is providing three quarters of South Australia’s power Paul Souders/Getty Images A DECADE ago, the main landmark in Port Augusta, a town in South Australia, was a 200-metre-tall chimney puffing fumes from a coal-fired power station. “You could see it from 40-odd kilometres out,” says Gary Rowbottom, who worked at the plant for 17 years. Today, however, there are no hints of this history. The chimney is gone and the sky is a pristine blue. The chief landmark now is a tall tower topped by a dazzling light, where sunlight reflected from 23,000 mirrors on the ground is focused to power four giant greenhouses in which tomatoes are grown. Next door is the newly built renewable energy park, home to 50 wind turbines and 250,000 solar panels. Port Augusta is representative of a remarkable shift that has swept South Australia. In 2007, just 1 per cent of the state’s electricity came from solar and wind. Now it is 73 per cent (see below graphic) – the highest proportion of any major grid in the world. On days that are particularly sunny and windy, it powers itself with 100 per cent renewables. That happened on 180 days in 2021 and for a 10-day consecutive stretch in December 2022. The state is now racing to ramp this up to renewable-only power year-round. Coming from neighbouring New South Wales, where just 31 per cent of electricity is from renewables, I find this clean energy rush highly enviable. It is also highly instructive to the wider world, which needs to rapidly wean itself off fossil fuels to avert a climate disaster. To find out how such progress is possible, I have crossed the border to meet those leading the charge. source: opennem.org.au South Australia covers almost 1 million square kilometres – more than seven times the area of England – but has a population of just 1.8 million. Almost 90 per cent of the state is desert, so most people live along the wetter, cooler south coast, largely in the capital Adelaide. The state’s renewable energy push began in 2002, when the South Australian Labor Party was elected to government. Its initial interest in renewables was in fact economic, says Tom Koutsantonis, the state’s current energy minister under its latest Labor government. At the time, South Australia’s electricity was very expensive, partly because its large, spread-out grid is paid for by a relatively small population, and partly because the previous Liberal government had privatised the state’s electricity assets “on terms that wouldn’t benefit consumers”, he says. Weaning off fossil fuels The Labor government wanted to “smash up the monopoly” of the newly privatised coal and gas-fired power stations to drive electricity prices down and “the obvious answer was renewables”, Koutsantonis tells me at his office in Adelaide. The government realised the desert could actually be a “massive opportunity” because it provided the vast amounts of space, sun and wind needed for competitive renewable energy generation, he says. In 2002, the government approved the state’s first wind farm on the Fleurieu peninsula. This opened the floodgates to more renewable energy projects, with 24 onshore wind farms and five large-scale solar farms now operating. In 2008, it also began incentivising households to put solar panels on their roofs by offering generous payments to them for any excess solar energy that was fed back into the grid. “We had this at our house and suddenly I was getting credits on my electricity bill because I was selling more than I was using,” says Jenny Paradiso, a former librarian in Adelaide who co-founded a solar panel installation business called Suntrix in 2009. As word spread, people rushed to get panels and cash in, she says. Now, more than 40 per cent of South Australian homes have them – one of the highest rates of uptake in the world. One afternoon last month, a major new milestone was reached when the state’s entire electricity demand was met by rooftop panels alone. The drive for solar power Certainly, as I drive around, the enthusiasm for solar is evident. There are panels carpeting the roofs of homes, shops, pubs and public toilets. I meet Adam Langham, a chemical engineer in the Adelaide suburb of Netley, who has 58 panels on his house and car port. They produce 12 times more power than he, his wife and two children consume. The government discontinued its subsidy in 2011, but smaller payments are still offered by private electricity companies, meaning the family makes more than enough money to pay off the upfront cost of the installation. “I’ve had quite a few friends call me up over the years and say, ‘OK mate, solar panels, what’s the go?’ and I tell them, ‘they’re a no-brainer – go for it’,” says Langham. Wind energy has also been received more warmly in South Australia than in New South Wales, where a planned wind farm near the town of Berrigan was recently scrapped due to a community backlash. One Berrigan resident told the local newspaper the project would “pose physical and mental health threats to our children”. Here in South Australia, however, there are framed paintings of wind turbines in my motel room in the town of Burra. Read more Renewable energy boom may help us limit warming this century to 1.5 ̊C What explains this difference in attitude? Fran Baum, a public health social scientist at the University of Adelaide, says one reason may be that South Australia has a long history of being progressive. It was one of the first places in the world to allow women to vote and stand for parliament, for example, and the first Australian state to decriminalise male homosexuality. Port Augusta’s coal-fired power station is gone. Today a solar farm dominates the skyline Gary Rowbottom Wind farm developers are also getting better at working with communities, says Tom Jenkins, who heads the South Australian branch of Neoen, a company that is building the state’s biggest wind farm, Goyder South. For example, it funds community projects near its wind farm sites, including local clubs and sporting teams; encourages its contractors to employ local businesses; and hires First Nations people to supervise construction in case of the discovery of artefacts or remains. For the Goyder South project, the company will also offer annual payments of AUD$1000 to $5000 to every household within 6 kilometres of a wind turbine as a goodwill gesture. I do, however, meet some people for whom the switch to renewables has been challenging. Rowbottom and around 400 colleagues, for example, lost their jobs in May 2016 when Port Augusta’s coal station, the last one in the state, closed. Few were able to find jobs in the town’s new renewable energy sector, which required fewer staff and different skills. Rowbottom initially had to move to Queensland to work at another coal power plant, but has since found employment back in Port Augusta. There have been other hurdles to overcome. In September 2016, South Australia suddenly faced its biggest test yet when almost the entire state experienced a blackout that lasted for days in some areas. “It was the first state-wide blackout like that in Australia in about 50-odd years,” says Christiaan Zuur at the Sydney arm of the Clean Energy Council, which represents Australian renewable energy businesses. The 2000-watt energy saving challenge may be hard, but it’s worthwhile A Swiss vision of a low-energy society set a goal that is irresistibly simple: consume energy at a rate of just 2000 watts. It’s a great way to push us to use less power - good for the purse and the planet The blackout was triggered by a violent storm that knocked over more than 20 electricity pylons and cut three of the four major transmission lines in the state. Coal enthusiasts in the federal government seized on the event to argue that renewables were unreliable. For example, Scott Morrison, Australia’s treasurer at the time, who became its prime minister from 2018 to 2022, accused the South Australian government of “switching off jobs, switching off lights and switching off air conditioners and forcing Australian families to boil in the dark as a result of their Dark Ages policies”. Koutsantonis believes the state’s supply would have gone down regardless of its energy mix, due to the severe damage to transmission lines. But the mocking that South Australia received made the government there determined to prove the naysayers wrong, he says. “We hated the ridicule we got from the rest of the country.” “After the blackout, a whole bunch of very positive things were put into place that have led to South Australia now being where it is – a world leader in terms of its renewables uptake,” says Zuur. In 2017, for example, the state government created a AUD$150 million technology fund to provide grants or loans to businesses that could offer new technologies that would make the grid more resilient. Backup batteries One project to get funding was a giant battery – the first of its kind in the world – to provide back-up in the event of major grid disturbances. It was built by Tesla following a famous bet on Twitter between Mike Cannon-Brookes, Australia’s best-known tech billionaire, and Tesla boss Elon Musk. Musk told Cannon-Brookes that Tesla would get the battery installed and working in less than 100 days, otherwise it would be free. Luckily for Tesla, it achieved this in 63 days. The battery is near Jamestown and looks like hundreds of refrigerators lined up in rows in a field. Each is filled with lithium-ion cells that are all connected to form one big battery with a capacity of 194 megawatt-hours. The facility monitors the frequency of the local electricity grid and if it suddenly rises or falls, the battery rapidly charges or discharges to stabilise the grid. This has since proved its worth on multiple occasions, including in August 2018, when lightning strikes caused widespread grid problems across the eastern half of Australia. Major blackouts occurred across New South Wales and Victoria, but the lights stayed on in South Australia, as the battery was able to rapidly reverse the sudden drop in grid frequency. Inspired by its effectiveness, Victoria and New South Wales have since built their own big batteries. A giant battery provides backup to the grid in South Australia Bradley Cooper / Alamy Stock Photo The same is true in several US states that are also ramping up their wind and/or solar generation. California, Texas and Florida have recently built or are building big batteries to help maintain the stability of their grids as they change their energy mix. Another innovative project that emerged after the blackout was a “virtual power plant“, also built by Tesla with some initial government funding. It comprises a network of solar panels and batteries that Tesla installed for free on more than 4000 government-owned social housing properties across South Australia. Tesla uses sophisticated software to coordinate the individual systems so they function like a single power plant. This allows it to trade surplus solar energy stored across the battery network on the electricity market. This appears to be a win-win for everyone because it makes money for Tesla, reduces electricity costs for the social housing residents and helps to stabilise the grid so that blackouts are less likely for the wider community. I meet Craig Renton, who lives in a social housing property in the outer Adelaide suburb of Elizabeth. He joined the virtual power plant in August last year and says it is “really good”. “My wife and I are pensioners and it saves us money – about AUD$60 a quarter – which makes a difference,” he says. Renton uses a machine to help him breathe at night and if there was a blackout in the past, “I had to get up to get the generator going, but since we got the battery, now the power comes back on within 5 seconds”, he says. Equitable access to renewable energy Renton says there is “no way” he would have been able to afford solar panels or a battery without the scheme. In this way, the virtual power plant is helping to address a key criticism levelled at these technologies, which is that they are typically only accessible to the wealthy. “One of the principles that we have in this energy transition is that we want to make sure we don’t leave anyone behind,” says Scott Oster at the South Australian government’s energy department, who has helped manage the project. Despite all this progress, however, average electricity prices are still higher in South Australia than in most other parts of the country. This has meant there has been “a bit of fatigue creeping in” among the community, with people questioning the benefits, says Koutsantonis. Electricity prices have remained stubbornly high because South Australia still relies on gas-generated electricity to fill the gaps on days when there isn’t enough sun and wind, and gas has become increasingly expensive in recent years, he says. Should we be worried about AI's growing energy use? The expanding use of large AI models demands huge numbers of powerful servers, which could end up consuming as much energy as whole countries As a result, the most pressing matter now is to find ways to store the excess solar and wind energy produced at particular times of day or on certain days, so it can be used when there is a deficit, instead of falling back on gas, he says. One solution may be to use excess solar and wind energy to power electrolysers that split water to make hydrogen. This hydrogen could then be stored and converted back into electricity when needed, either by burning it or feeding it through hydrogen fuel cells. To test this idea, the state government will commit AUD$600 million to building a hydrogen power plant near the town of Whyalla, which is due for completion in 2025. If it works, the state will be able to meet its target of running solely on renewables by 2030 and will probably have the world’s first large fossil fuel-free grid based on solar and wind energy. “If we can decouple ourselves from coal and gas prices, we decouple ourselves from international price shocks, and then all of a sudden the cost of power is just what it’s costing us to generate it,” says Koutsantonis. A massive solar farm powers a tomato farm in South Australia Gary Rowbottom According to Zuur, there is no reason why other parts of the world couldn’t replicate South Australia’s rapid adoption of renewables. The state has certain advantages, including large amounts of space, sun and wind, but other places can tap into their own advantages, he says. For example, nations with less land, like the UK and Japan, have built wind farms offshore, while Iceland, which gets little sun, uses alternative renewable resources like hydropower and geothermal energy to generate almost 100 per cent of its electricity. Personally, seeing what South Australia has achieved in a relatively short space of time has filled me with optimism that the world will be able to wean itself off fossil fuels sooner than we think. Although its energy transition hasn’t been perfect, it has shown that the key ingredients for success are strong political leadership, winning community trust, willingness to try new technologies, equitability and, most important, never giving up. Alice Klein is a New Scientist reporter in Sydney, Australia

I'll let my wife know 😉 Rough cut pine / spruce. Graded. Grooved. Primed. Painted. Never again. Use Ruukki roof or full-PV roof and pre-painted pre-machined thermowood boards intended for cladding and save your sanity. 😉

You need gully traps on both of those before the 110mm pvc. And orange pvc pipe has to be fully buried as it's not UV stable. And do your drainage plans allow you do discharge directly to a watercourse without attenuation? In reality, the way you've done it will be fine, bar the odd blockage you might have to deal with in autumn. But if this is works involving BC, it'll fail.

Yeah, absolutely agree with this. Fitting weep vents is trivial, and even fitting cavity trays is pretty straightforward for a brickie. They get a lot of practice for retrofitting trays when building extensions so it won't phase them at all.

Gratitude to all. I lifted the manhol cover. It is not a raised one as it was originally dug in the middle of the drive (before we bought the house). THe shaft is bone dry and the metal 'tube' through which the pump can be extracted is sound and waterproof. Further inspection reveals that the surface water is running through loose gravel on the drive and collecting at one edge of the manhole cover which had not been placed correctly allowing a few bits of said gravel to prevent the lid from sealing onto the rubber 'washer'. That has now been cleared. the water still 'rushes' when the rain is heavy, but I am sure now that the bore hole is completely dry. I'll keep you posted! CHris

Yes. Plastic is much easier. Plus you shouldn't leg metal touch thr ground.

Well if you take the average household gas usage of 15 MWh and divide it by three, then multiply it by 30 million, you get an extra demand of 150,000 GWh. If we say that an average car does 12,000 miles a year, and does 3 miles to the kWh, then with around 30 million cars on the road, 120,000 GWh. So an extra 270,000 GWh a year. Now the car mileage is probably evenly distributed, so 10,000 GWh/month. Heating is probably similar to our current electricity demands, so 55% of it spread over 7 months. So a monthly mean of around 12,000 GWh/month, but varying between 8,000 and 15,000 GWh per month. So at worse, somewhere around 25,000 GWh extra. Divide that by the 31 day sin December (probably the worse month on average) then that is 810 GWh/a day. Daily usage is currently around 804 GWh/day. So we need to double the land area and the costs. Still very achievable (if my sums are right).

the network operators are very aware of that issue. Up here in the sparsely populated windy north, where a lot of new wind power is being built. They are upgrading the grid as fast as they can to carry all this newly generated power down south to where most of it is needed. But it seems to be a slow process. There are already pinch points on the grid where it is already at capacity and that is limiting new generation coming on line. It has been at least 5 years, probably much longer since the plan to build a third HV grid connection from the far north to the Central belt was first proposed. The section of line that will pass near us is now in the public consultation of it's third proposed route. It has not even got as far as a formal planning application. To all those "stop oil" protesters, I say it is no good telling the public to stop using oil. You need to be be lobbying the government so that the necessary upgrades to the grid to enable the full potential of wind power, does not get bogged down in a 10 year planning battle before they can even start the 10 year build program to implement it. The government needs an honest discussion. Do we carry on as we are, and take a VERY long time to plan anything like this, so we "get it right" or do we adopt what some countries have and "do it regardless" because it is important. It will be quicker but there will be a lot of people moaning they were not given the chance to object. You can have it quick, or you can have it right, but not both.

1. Do you need an outlet at the other end? With the tapered outlet you have, the gutter will empty quite fast: much faster than with a downpipe sized outlet. 2. Don't break the slab. But it looks as if you could take the pipe to the right until after the slab. ..or use more bends to loop it out and down.

That’s very interesting but what extra demand is going to be made when we all have heat pumps and EV,s? I have not seen anything about covering that extra demand. I still say insulation of housing stock is a missed opportunity, helps the poor and lowers demand.

We've got lots of suitable offshore for large wind farms, and just think of all of those acres used to grow biofuels (The last published ONC figure was 120,000 hectares in 2020) and could convert this to PV or agroPV (e.g. grazing livestock under the PV cover). With some battery and extra pumped hydro we could easily get over 80%.

No we need better laws such as the one in Singapore - 'for the greater good', basically 'shut up, your feelings don't matter, we are doing it'. Because it provides more benefits to people or the environment, than just you.

When you take seawater and make hypochlorite, which they have been doing for decades offshore, for local injection into seawater lift, to kill of marine growth in piping systems and heat exchangers, one of the byproducts is hydrogen.

Had pre plaster inspection done today So can push on with the boarding 350 boards arriving Wednesday So early night on Tuesday 😁

I disagree with buying the absolute cheapest. There’s lots of carp out there that will start causing problems pretty soon if you fit a house full of them. Why buy the real budget carp, when proven good quality gear is only pennies more. I usually use scolmore click. Fit thousands a year and can’t remember the last failure. Hager is also decent. MK Logic Plus is ok, but overrated and priced. Legrand are decent. Just fit click though is my advice. Very well priced and bulletproof. https://mastertrade.co.uk/scol-cma036-click-cma036-socket-2g-switched-13a-whi.html I’d advise against CEF, unless you like getting tucked up. It’s possible it’s an acronym for Check Every Figure

https://www.newscientist.com/article/mg26034621-600-how-countries-can-go-fossil-fuel-free-with-wind-and-solar-superpowers/

Had an Ideal Logic Combi 35kWh boiler at my last place doing 2 bathrooms. Yeah the pressure dropped a little when using both, but that was infrequent enough that it didn’t bother me. the temperature certainly never dropped regardless. If I wasn’t going heat pump this time round I’d have no hesitation about chucking in a big combi again. I really liked that I didn’t need to think about hot water. It was just available all the time.

So eventually got E7 tariff yesterday, after the failed attempt to getting a smart meter working. Also got the Home Assistant GivTCP, automation for the battery inverter working (been trying that for the past week). It reads the expected solar production, from a solar forecasting site, it also collates your usage data and sets the battery state of charge level accordingly, to only cover what's required. Yesterday the state of charge was set to 64%, we didn't run out of battery energy before the next charging period. Last night the charge was up to 78%, as less solar is expected. Have the ASHP charging the floor in the low tariff period also, at the moment it's running anywhere between 3 and 5 hours, running off the time clock in the thermostat, basically we bump the demand temperature up 1 degree at the start of the low cost period and back down to normal target temp about 5 hours later, if the ASHP needs to run longer on very cold days it can. Yesterday we used 0.5kWh peak electric. Everything else was off peak and from the battery and a little solar. The 0.5kWh is the small amount the battery seems to send back to the grid all the time, not sure if it's as a reference value or what? Our average winter electric consumption last year was 13kWh a day with gas heating. We have added a garden room, which my wife uses daily and that it is heated by an electric heater, yesterday it used 5kWh. Yesterday our electric consumption including our normal house usage, heating with the ASHP, and heating the garden room, we imported 18.7kWh @ 15.16p per kWh.

Slightly off topic I e been suprised by the amount of care LABC Warranty have taken Half the price of Protec 7 visits Looked at everything Our previous made 3 visisits Inspected the foundations from his car Roof from the ground Ten minutes in out kitchen for the final inspection

This just highlights how easy it is for countries with low population density, abundant land, and a warm sunny climate to go completely green. Not so easy for the UK with a much higher population density, not so much "spare" land, and a much less sunny climate. Oh and tight planning regulations. We can see the difference in the UK. Orkney for instance produces more green energy than it can use. Easy on a low population windy group of islands. Even Scotland as a whole with it's low population density, lots of coastline for offshore wind and already a lot of onshore wind should be able to generate it's own green energy. Not so easy for the SE of England with it's high population density and not much "spare" land.

Yes. I blame the IT industry, everything has to be reduced to a 0 or 1, with 0 being wrong and 1 being right. The main thing is to reduce usage, there was a bit about food waste in the USA, apparently a third is wasted (and they start with a lot more). The emissions from this waste was equivalent to 55 million tonnes of CO2. About the same as running 12 million gasoline cars (and they are not the most economic cars in the USA).

Id allow £2k/m² for the new bits plus £1k for the rest of the house. Think you're looking in the £300k ballpark. Budget kitchens and bathrooms etc will go someway to keep this lower, but hard to reduce the core construction costs.

This was in my comic. I knew the hydrogen had to be 'clean' to run though a fuel cell, never thought about the water that makes it. Can we get limitless green hydrogen by splitting seawater? Electrolysers that split water to produce hydrogen have trouble working with seawater, but overcoming this would offer new ways to produce the clean-burning fuel using offshore renewable energy By James Dinneen 25 October 2023 Seawater could be a limitless source of hydrogen, but we need electrolysers that can handle the high salt concentration Shutterstock/andrejs polivanovs The following is an extract from our climate newsletter Fix the Planet. Sign up to receive it for free in your inbox every month. 97 per cent of the water on Earth is in the ocean. If even a small amount of that could be harnessed to make hydrogen using clean energy, it would provide a practically limitless source of clean-burning fuel that would accelerate the transition away from fossil fuels. But there’s a catch. The devices currently used to split water molecules to make hydrogen — called electrolysers — require ultra-pure water to function. And seawater is full of dissolved salt, other minerals, metals and microorganisms that degrade components and gum up the works. Recently, researchers have made headway on solving these problems. Some are pushing ahead with plans to make hydrogen from desalinated seawater, while others have developed new electrolyser designs that could be attached to offshore wind turbines to make hydrogen directly from the ocean. Success here would not only reduce the demand for freshwater to make the fuel, but also expand the range of places where it makes sense to produce hydrogen. Something in the water Hydrogen will play an increasingly important role in decarbonising our energy systems on the way to net-zero by mid-century. The clean-burning gas can be used to store and transport energy, and it can power things that are difficult to power directly with electricity. The latest projections from the International Energy Agency see global production of low-emission hydrogen increasing rapidly, with planned projects amounting to 38 million tonnes per year by 2030. Sign up to our Fix the Planet newsletter Get a dose of climate optimism delivered straight to your inbox every month. Sign up to newsletter There are a variety of sources of low-emission hydrogen, but most of it is set to be made by splitting water molecules using renewable electricity, making what’s known as “green hydrogen”. The main limitation now on green hydrogen production is access to cheap renewable electricity. But as hydrogen production increases, access to water could also become an issue. “We need to avoid creating a situation where there is competition between water that we need for drinking and water that we need for fuel production,” says Pau Farras at the University of Galway in Ireland. Estimates vary for how much water might be needed for hydrogen production – and some argue the problem is overstated – but Farras says producing hydrogen could eventually account for as much as 20 per cent of water use in some places, especially where there is scarce freshwater. Using abundant seawater would avoid this problem. Splitting seawater could also enable new ways of combining offshore renewable energy with hydrogen production, expanding the geographical range of both. This possibility in particular has driven new interest in splitting seawater. For instance, in March the Netherlands announced a plan to build a large offshore electrolyser in combination with an offshore wind farm in the North Sea. The hydrogen produced there would then be sent back to shore via an existing natural gas pipeline, avoiding the need to lay expensive new undersea transmission lines. At least 10 other major projects combining offshore wind and hydrogen are in the works elsewhere, including several off the coast of the UK. For wind farms built more than 50 kilometres offshore, it could actually be cheaper to transport the energy they produce back to shore as hydrogen via ships or pipelines rather than as electricity via copper wires. Researchers at the technology firm Siemens, which is investing large sums in wind-t0-hydrogen technology, even envision automated “production islands” that use seawater and offshore wind energy to continuously make hydrogen and other chemicals like ammonia to refuel ships sailing by. Stripping salt A big problem for these futuristic visions, however, is that seawater is poorly suited to the finicky chemistry of electrolysis. Even normal potable water requires extra purification steps before it can be used in a conventional electrolyser, says Alexander Cowan at the University of Liverpool in the UK. “Seawater is the extreme.” In an electrolyser, water — H2O — is run past two electrodes. Hydrogen atoms move to the negatively-charged cathode, while the oxygen atoms stay near the positively-charged anode and are released into the atmosphere. Normally, ultra-pure deionised water is used in this process. Using seawater, with all its impurities, causes problems. The dissolved salts and minerals degrade many of the catalysts and other components used in the devices, so they wear out very quickly. Running electricity thought the water can also oxidise chloride to produce corrosive chlorine products. Biofouling from microbes growing in the water is another issue. “If you have a biofilm on top of the electrodes your reaction is dead,” says Farras. A hydrogen refuelling station in Tenerife, Spain Lucia Villalba One way around these problems is to desalinate the seawater before sending it to the electrolyser. On Tenerife, one of Spain’s Canary Islands, Farras and his colleagues have installed a self-contained system that uses desalinated seawater and solar energy to make hydrogen using a conventional polymer electrolyte membrane (PEM) electrolyser. Farras says officials were interested in the project to reduce the island’s reliance on imported fossil fuels. The system, which is the size of a 12-metre shipping container, can now produce up to 65 kilograms of hydrogen each day, which Farras says would be enough to supply two to three hydrogen fuel-cell powered buses and several cars. His team is now in conversations with Tenerife’s transport administration to fuel public buses with hydrogen next year in an effort to “kickstart” demand for hydrogen on the island. Using desalinated seawater for hydrogen production makes sense, especially where substantial desalination capacity already exists, says Farras. The hyper-futuristic Saudi Arabian city of Neom, for instance, is supposed to include a facility that could produce 600 tonnes of green hydrogen a day using desalinated water from a plant that will also supply the city with drinking water. Going direct However, desalination isn’t an ideal solution. It adds to the energy requirements of making hydrogen, and may be poorly suited for smaller, more distributed systems, says Zongping Shao at Curtin University in Australia. Another approach is to design electrolysers that can work directly with seawater, thus avoiding the need for a separate desalination step. There has been a flurry of research on how these seawater-hardy devices could work, with a variety of designs. According to Cowan, they fall into two broad categories: some involve using membranes to purify seawater before it flows through the electrolyser, and others use different components or designs that are more robust to seawater. In one design, Shao and his colleagues sandwiched an electrolyser between special Teflon membranes and then ran seawater around the outside. The membranes enabled water vapour to diffuse into the electrolyser while leaving impure components outside. In a study published last year, this system continuously produced hydrogen using seawater in tests for at least 3200 hours without any noticeable changes in function. “That could change the calculation,” says Cowan. “If you could run something for years without much maintenance that’s interesting.” Read more Waste plastic can be recycled into hydrogen fuel and graphene Another approach, taken by Daniel Nocera at Harvard University and his colleagues, similarly purifies water before it reaches the electrolyser by passing it across a membrane. As the water molecules are split on one side of the membrane, this maintains a concentration gradient that draws more water through by osmosis. Daniel Esposito at Columbia University in New York and his colleagues have done away with membranes entirely in an effort to make cheaper, more robust electrolysers. A company he co-founded called sHYp is aiming to commercialise these membraneless electrolysers by pairing them with a proprietary saltwater processing step that produces other valuable byproducts, such as magnesium hydroxides that could be used to make carbon-negative cement. According to the company’s CEO Carl Fischer, the processing unit works by increasing the alkalinity of the seawater before it reaches the electrolyser, which he says avoids biofouling and unwanted reactions with chlorine. He says the company has pilot projects planned for next year in the US, the UK and Europe, including plans to install the electrolysers on offshore wind turbines and at ports. Horses for courses Cowan says that while many of these methods of direct seawater electrolysis are promising, at scale they are likely to suffer from some of the same problems as conventional electrolysers trying to manage the complexities of seawater, such as biofouling from the ubiquitous microbes that live in the ocean. Farras also has doubts about this approach. “You can work around these problems in the chemistry. But I don’t think you can work around the biology,” he says. “Direct seawater electrolysis is a fantasy.” Even if the direct approach could be made to work at scale, Farras says it may be unnecessary in contexts where large-scale desalination is already available. Desalination adds to energy requirements, but only a small amount when compared to the energy demand of electrolysis itself. However, Cowan thinks direct electrolysis could have its uses, especially for remote places where large-scale desalination might be impractical. It could also be key for the many projects aiming to integrate electrolysis with offshore energy production, opening valuable space on offshore platforms that would be taken up by a bulky desalination operation. Further, he says research on directly using seawater could lead to more robust electrolysers in general. These could use wastewater, or simply better withstand the inevitable impurities in any water on its way to becoming fuel.

Yeah it's the way it is towards the end of the build. We found these to be a very good price. https://www.internaldoors.co.uk/mexicano-modern-veneer-oak-door

Facebook marketplace. If you have a vehicle you can pick doors up in, you can get a set for under £50. Or free because people can't get rid of them. Depending on your house size you might need 2 sets which won't match, but they'll tide you over. I got a still-shrinkwrapped Wickes £30 door for free that way.

I presume you’re snuggled under a quilt with a room that temperature? Without any heating our bedroom temperature is 21.5 degrees, as is the rest of the house +/-0.5. We’re sleeping under a quilt cover (no quilt) and we do so for >90% of the year. It’s like summer night bedroom temperature all year round. I’m guessing that currently you don’t achieve your desired 15/16C in the summer? You’ll adapt.

Actually it's not always the temperature of the air that prevents you from getting a good night's sleep, it's the quality of the air also. Low CO2 and Particulate Matter (PM) has a huge influence on your sleep. Luckily a good MVHR system should help you achieve that.

Who ever installed/commissioned the UVC. The Benchmark Certificate comes with the cylinder in the back of the user install manual. The installer has to leave the user install manual with the end user as it's also the record book for servicing.

Sorry to hear that! For SAP you need a (Full) SAP assessor. I think you need to know what they mean by 'heating certificate', because I am not sure I do. Elec cert should be OK if your spark is a member of a self-cert scheme. Unvented Cylinder Benchmark Certificate - not sure who you get this from but I doubt it should be difficult. 'Any Other certificate...' - MVHR? Best of luck.

The biggest problem is going to be the warmer months. Changing the air 0.5 times an hour, or 10 times an hour, via MVHR or not, is not going to help if the OAT is close, or above your ideal temperature. You may have to factor in some cooling. Personally, having grown up in the tropics, I like a warm bedroom. It can take a few weeks to get used to it, but then I sleep as well as I ever do. And getting up to a warm house is lovely.

That differs to my findings, it is a long time since I have regarded MK as "quality" I have had lots of problems with jammed screws in new MK sockets, jammed to the point you can hardly turn them, and I am not alone.

If it is a 3 phase board I can easily see it costing that much, but equally it would have to be a very rough 3 phase board to warrant ripping it out and replacing. So it's a 16A circuit for the kitchen at present, I agree that is too small for microwave and kettle, regardless of what diversity says, they WILL be used at the same time. So that's north of 20A. You need to find if it's just a radial circuit at the moment and of so what size cable. It could be feasible to convert it to a ring. It is pretty normal for tenants to be responsible for electrics in commercial. One unit I know which the owner bought for his own use has a REALLY old rewireable 3 phase fuse box well past it's best, but it is still there as no tenant has paid for an upgrade.

Don't re invent the wheel. Look at Exhaust air Heat Pumps that are usually built and packaged with a hot water system to do exactly what you describe. Where in the UK are you? I am skeptical that any UK house can really run all year with no heating,

Welcome to the forum. First of all good luck with your project. We lived in East Kent at the time and it took us eight years to complete the building work and two years planning, so it pays to have somewhere comfortable to live, while all that is going on. We also had an old bungalow which we replaced with a Passivhaus. We were able to live in the bungalow while building the house in the garden, which was a tight squeeze, but at least we were always on site. We built a timber frame on an insulated slab and did a considerable amount of the work ourselves, hence the eight years. We had never done any large building work before, but we designed and built our own Passivhaus, so just pace yourself and enjoy the rollercoaster.

Welcome. What sort of engineer are you? With any project, make the big decisions first, then stick to them. You don't want it to end up like HS2. Design in the PV and the ASHP right at the start. That will make it a much cheaper place to build. Don't add complications.

Run a dedicated towel rail circuit to the pair of them and put them on a timer, immersion heater timers work well, or something a little more fancy, and just set a schedule, that is the simplest. Or you might want to split the circuit, i.e. if one is in a infrequently used bathroom you might not want it on at all unless you have guests? In which cause schedule the main bathroom towel rail to suit your typical daily schedule and put the guest bathroom on a simple on/off switch which can be switched on while they visit etc. I've also seen them linked to PIR sensors in the bedroom/hallway - the idea being that if people are about then the chances are they will use the bathroom at some point, that then automatically adjusts for when you are away for the weekend etc.

I have used Fermacell many times. Just follow the system. All the guidance is there. Use their screws, joint stick, filler and fine surface treatment. I cannot plaster but I can finish a Fermacell wall myself better than any plasterer can finish any plastered wall without making any mess than I cannot vacuum clean. For mounting stuff to walls like a kitchen, utility or bathroom there is no other choice for me. You can screw kitchen units to it, boilers, radiators, inverters. No pilot holes, no plug just 5mm wood screws. Yes it is heavy. It’s harder to cut which is why plasterers slag it off. You don’t need edge bead. It is recommended to put SBR on it prior to tiling in humid areas. I cannot see why a taper edge version is required at all. I have never used it. Personally, I found it is better not to use the jointstick. Simply leave a small gap and fill it with the Fermacell filler. Sand off and then go over with FST using a squeegee. FST is not a skim, it fills the pores and gives a uniform texture. If painting a good quality paint helps. The decorating lady prefers Johnson’s Jonmatt. Johnson’s Durable Acrylic is good for bathrooms. since it was bought out by Hardy outfit, they have tried to kill Fermacell in the U.K. The necessary materials like filler etc became hard to find. It used to come from CCF and the like but is scarce. Any plasterer you speak to will say it is rubbish but that is because they don’t understand it and never learn. It takes more words than you can fit on a beer mat to explain how to use it.

@willbish are you running your UFH directly from the ASHP water pump? If so, any issues so far? And also do you know how the ASHP actually controls the pump? I’m planning a similar simple system. Monobloc ASHP directly feeding UFH from internal pump without any buffer, zones or thermostat. Whole system one zone and weather compensated based on heat loss of the property (and also a three port valve for DHW but that’s standard). thanks

You're better off keeping the wind out of your cold loft. Breathable membrane taped at all joints. Batten and counterbatten and ventilate above the membrane. Attached are diagrams from proclima and tyvek and a greenbuildingstore video that from 3:30 discusses Thermal Bypass. Pro Clima

I've quoted recently for 48m2 worth of windows and the prices range from £356 to £485 per m2. You can see a chart of them below: PM if you want the breakdowns in excel! Edit: X axis is the area averaged U value of the whole window (glass and frame combined)

It is to connect up Hinkley Point. They will probably have to take them down again.

Two news items this week on TV, with the people being interviewed in tears, one complaining about a proposed wind farm, calling it a ring of steel and the other a solar farm. And both stating they are all for renewables, but, basically as long as it's somewhere else

Cor, You don't hang about do you! Pre plaster is my next inspection... BI keeps popping round to have a nose though, because taking too long, popping cards into the post-box, he's more impatient than the wife!

If sized correctly they should not notice it. My neighbours cars are less than 10 metres away, I don't notice them. But the dickhead that is 40 metres away I do. He still thinks that to start a vehicle you turn it over still it catches, then flatfoot it for 30 seconds. Now where is that old can of expanding foam, a squirt up the exhaust should muffle it a bit.