Geology trivia: An Sgùrr, the shapely wee hill that features in the pics, is interesting as it started off as a valley that was filled with lava and ended up lasting longer than the surrounding rocks
There's no doubt in my mind that this is the way power is going. I might still be alive to see the last coal/oil/nuclear power stations get switched doff.
I hope not. I would love to see more nuclear stations switched on. Solar and wind is not going to be sufficient for providing baseline power without great increases in storage potential.
You'd be terrified to know that some utilities will actually disable your AC or electric water heater remotely during periods of peak power usage if you've agreed to receive a discount for them to do so.
Everything is rationed, it's just normally done with tradeable allocations. There are plenty of people on the mainland whose electricity goes off from time to time because they can't afford to put money "in" the meter. A more acute form of rationing in some ways when people around them can afford more energy than they need.
It means everybody's bill can be lower than if they had an additional generating facility that they only sometimes needed but still have to pay off all of the capital and maintenance costs, and possibly fuel if it is a diesel plant which is typical for small islanded systems.
I think it is a victory if the community can work together to use less power when there is less supply rather then people using as much as they want and forcing rolling blackouts.
Because we literally handed over a piece of paper yesterday formally starting the process whereby we'd leave the EU. I suspect the parent feels like this is a project that might not have had access to this kind of funding outside the EU in an independent UK
Where do you think the money for the funding came from?
Net contributors to the EU, like the UK. We gave the EU more than they spent on us (of course, because there are poorer European countries).
You make it sound like you think EU funding money was a gift from other people. It was them doing us the favour of giving us some of our own money back.
If we choose to, we can spend exactly the same money in exactly the same way. Or we could democratically decide amongst ourselves to do something different with it.
It is my opinion that a small-scale renewable energy project on an island community of <100 people would be unlikely to get 1.66M GBP from the UK government. Perhaps the Scottish government would want to, but have considerably less means to do so as they still have a relatively modest budget.
You're telling me that the benefit of the EU was that it was an effective way to bypass the people's democratic representatives when they won't do what you personally want?
> would not get 1.66M GBP from the UK government
They did get 1.66M from the UK government. It just went involuntarily via the middleman of the EU.
There's countless areas where the national govt has shown no interest in for decades, which have now received development funding from the EU. If that's what it takes to help these places I frankly do not care that was allocated by someone in another country.
However don't try to make it like this is my single pro-EU issue. This is just one small example of a thing I like.
>the benefit of the EU was that it was an effective way to bypass the people's democratic representatives //
The EU is democratically representative too, in a very similar way to the UK parliament. They have the same shortfalls. It just happens that across the EU there is more support for solving the energy crisis than there is in UK Conservative government. In part that's because IMO the EU looks more long term whilst the UK government appears only to be concerned about getting through the next one election. In part it's because the liberal and green elements that aren't properly represented in the UK, because we lack proportional representation, don't get to pressure our government locally but do get to represent the demos in the EU. It's the EU's better, ie more representative, democracy that causes the leap-frogging.
>They did get 1.66M from the UK government. //
Not really, sure the UK provided their part share of that, but they were forced to by the elected EU layer of government. The major share came from the other EU countries. Germany pays around twice the contribution of the UK and with France, Italy, and Spain we pay about 50% of the contribution. So the money is about 0.83M from these 5, perhaps about 0.2M from the UK government.
>involuntarily via the middleman //
The UK voluntarily, through a democratic process, joined the EU. The nation chose to put itself in the position where it would contribute the 0.2M and the other countries would add their 1.5M to enable projects such as this all across Europe.
David MacKay FRS is the Regius Professor of Engineering at the University of Cambridge. He studied Natural Sciences at Cambridge and then obtained his PhD in Computation and Neural Systems at the California Institute of Technology. He returned to Cambridge as a Royal Society research fellow at Darwin College. He is internationally known for his research in machine learning, information theory, and communication systems, including the invention of Dasher, a software interface that enables efficient communication in any language with any muscle. He was appointed a Lecturer in the Department of Physics at Cambridge in 1995 and was a Professor in the Department of Physics from 2003 to 2013. Since 2005, he has devoted much of his time to public teaching about energy. He is a Fellow of the Royal Society.
Nine months after the publication of 'Sustainable Energy - without the hot air', David MacKay was appointed Chief Scientific Advisor to the Department of Energy and Climate Change.
Excellent book and a thoroughly nice chap. He also name-checked my business as an example of a nice effective energy product at a DECC event a few years ago, which was flattering and unexpected (radfan.com for those interested).
What an excellent idea, Simon - I've been quite annoyed at the idiot-level old radiators we have in our rented accomodation, ruefully watching them waste my cash each winter.
I've bookmarked your page - I'll pay you a visit in Autumn!
You should build a little battery operated fan that you open your dishwasher door a little bit and set it in there to gently circulate some air to do the final evaporation that dishwashers cannot do, you would sell millions of them.
Couldn't manufacturers just add a low level fin/spoiler to the top of the rotating water outlet ["spray bar"/"spray arm"], run the rotation at low speed as a fan. Seems all the tech barring a slight raised area to catch the air a little is already built in; even just slowly rotating the "spray bar" unmodified probably would give enough air-flow? I can't imagine I'm the first person to think of that [too late to patent it!] bet you there's a company that has/had it as a feature?? One might even pump air down the spray bar using the systems already in place but with no water-flow; residual heat in the pipes might aid the process too?
FWIW some dish-washers have a built in fan eg "TurboHeat Dry" on Kenmore.
I paid like $500 extra for the auto-open feature on my Miele, but even getting that spendy, the fan only runs for ten minutes after the door opens, so some things still can be a bit damp. It infuriates me that they went to this complexity, but then don't let you lengthen the fan runtime. It's almost like they want to minimize your happiness per $.
Most of the dishwashers I've seen don't actively drive the rotating spray bar. It's spun by the water running through it and being ejected through angled holes.
You'd need to run a air blower into the same plumbing to make it do anything, and you'd need a fair bit of air to produce the same thrust.
I've been looking at radiator efficiency and last time I removed a radiator when decorating considered adding the foil backing to the wall but indications were that the cost of the foil in resources outweighed the benefit over something like a 10 year period, which surprised me.
Radiators have always bothered me since high-school physics in that the rhetoric that radiators are placed under windows to increase convection and circulate hot air never seemed quite to fit for me. It always _seems_ to be sending heat out the window.
In practice - referencing your https://cdn.shopify.com/s/files/1/0195/5444/t/45/assets/proc... image - what is supposed to happen is that the cold air is drawn in to the bottom of the radiator, rises over it, passes up and moves across the ceiling, falling as it cools and then being drawn back to the radiator.
Do you have any independent corroboration that radfan improves heating efficiency, or when used increases apparent warmth for the same cost of heating? I see you don't claim efficiency gains on the page but only appear to claim for "better" distribution of the warm air .. warmer air still rises though, right. But in the video you say "warmer home or your money back" which suggests you've proven it makes efficiency gains??
Good idea, would like to see some scientific work on the efficacy though before I'd commit to buy.
Thanks for the comment, sorry for the slow reply. You're right that radiators should effectively circulate warm air on their own by drawing in cool air, accelerating it up with a chimney effect and then expelling the warmth out into the room via a warm buoyant plume and so set up a cyclic convection current in the room. This should cause a nice, even heat profile through the room with minimal thermal stratification. Back when we had single glazing there was an extra benefit as the radiator provided a thermal curtain/buffer from cold air falling in from the window and the cool air falling in, mixing with the warm air would divert the buoyant plume and help destratify the room (hence why radiators are typically under windows).
Now that we have double glazing the latter doesn't happen and the circulating convection current that the former is supposed to set up never really materialises as most rooms have obstructions that stop the full circulation of warm air and simply cause the warm air to rise to the ceiling and stay there (we've seen 10degC floor to ceiling temperature differences but the typical is around 4/5 degC).
The Radfan helps set up that warm air circulation/cyclic convection current by essentially giving the radiator a little top up to get the air moving. It also reduces heat loss through the window by about 35% by diverting the flow of air away from the window a bit.
The testing we have done is twofold, field trials with 10 housing associations to see what the behavioral impact is but more importantly we have had controlled and independent testing carried out by the Salford University Energy House (http://www.salford.ac.uk/research/best/research-groups/appli...) that corroborated our own in house testing that showed the Radfan acted as a destratifier (temperature at the ceiling decreased and the temperature at sofa height increased by the same amount), reduced the heat lost through the window, allowed the central heating to turn off sooner (providing a small energy saving that more than offsets the running cost) and most importantly didn't introduce any forced convection on the radiator so the central heating wasn't working harder as there was no extra energy being extracted from the radiator (just a redistribution of the thermal energy already in the room).
The data shows that a Radfan will typically decrease the temperature at the ceiling by 1 to 2 degC and increase the temperature at the vertical mid point by a corresponding amount. It varies from home to home and in a very small percentage (less than 0.5%) it has minimal impact, hence we offer the warmer home guarantee so that if a home is in that small 0.5% (which we are unable to define as homes vary so much) then you can return for a full refund - we only want people living with a Radfan if they feel the benefit.
To be fair, Eigg is hardly a big consumer of electricity. I was there in December of 2006. I was staying in the guest house --- there's only one. I was the only tourist there. At one point I was kidnapped and taken to their community nativity play (which was actually a lot of fun). But the population is only 83, so running the whole place off renewable energy isn't difficult.
Fuzzy pictures from my trip here; the first few are from Mallaig, the other end of the ferry link:
...addendum: there's actually a huge pile of small power generation facilities springing up all over the Western Isles and nearby mainland. But the purpose of most of these is to produce passive income.
e.g. in Applecross on the mainland nearby, they're just finishing installation of a community-funded hydro system. It'll produce 90kW, with an income of about 100k GBP a year going towards the community and small shareholders: http://www.applecrosshydro.scot/
90kW is a toy, though. It's not going to provide energy independence for anyone. Rather more significant is the estate across the loch from my father's village, which is installing 3.5MW of private hydroelectricity: http://www.hydroworld.com/articles/2016/06/gilkes-begins-con...
But a 3.5MW plant, if we assume it runs at 100% capacity for a year, is going to produce 0.02TWh of energy, which is about 2 ktoe (kilotons of oil equivalent). In 2015 the UK used 140000 ktoe, of which only about 20000 ktoe are electricity. (https://www.gov.uk/government/uploads/system/uploads/attachm...)
These systems are important locally, but they're not going to run cities.
Edit: misread one of the graphs, corrected the number above. (The stupid graphs all have lines in slightly different shades of bodily function. Maybe they were trying to make a point.)
Energy independence on the personal level is as much of a pipe dream as economic independence. You might be able to achieve it at great expense, but what for? Even on Eigg the islanders are on a little grid.
That's a really cool site. Thanks for linking to it.
...but I do need to point out that 12% of electrical demand is about 1800 ktoe, which is only about 1% of total energy demand. We use about six times more petroleum energy that all electrical demand put together.
That's a tricky/misleading comparison to make since most of that oil energy is lost as waste heat, possibly 2/3rds of it. You really only want to compare the actual energy that makes it through to achieving some stated goal like moving a car or heating a home.
Well, yes. That's the great unanswered problem of the world; what do we do when that runs out or we can't burn it without exceeding safe CO2 limits?
Scotland already went through a period of energy resource shortage in the 1800s when there were very few trees left. Going back to only locally renewable resources might be like that again.
Well, my preferred solution is gigantic offshore tidal power generators in the Minch and around the top of Scotland where there are strong currents, preferably combined with hundred-kilometre-wide offshore wind farms (if you're building power generation structures in the open ocean anyway, you're an idiot if you don't put massive wind turbines on top of them).
Tide is one of the few renewable technologies that generates reliable power, and so is suitable for baseline load. Even in Scotland, the wind drops. But it's had very little investment, partly because of a poor reputation from horrific ecological damage caused by tidal barrages in the past, but mostly because wind is sexier.
But plants big enough to actually make a difference are going to be very, very big. Microgeneration is great for small rural communities, but we live in cities these days.
So that tidal lagoon... Is it basically a two-way dam that's taking advantage of the height differential between the interior and exterior? That's a pretty cool way to do it. Seems much simpler and more reliable than those wave-powered things that come out in news articles every once in a while.
Its been a while since I worked in the field but I'm pretty sure the main sources of electrical power in Scotland are the nuclear AGR sites at Torness and Hunterston B.
There is a similar electricity tracker at http://energynumbers.info/gbgrid . The main notable difference is that this one adds embedded wind to the window power total. Embedded wind refers to power stations which aren't connected to the metering system so they will show up as lowered demand (the tooltip for wind on the gridwatch site mentions this).
> But the population is only 83, so running the whole place off renewable energy isn't difficult.
No, but then there's only 83 people to distribute the costs over as well, and a consequent lack of economies of scale.
For instance, from the article, they have four wind turbines, each 6 kW; I'm sure the multi-MW wind turbines used in larger wind parks produce power at a significantly lower price/kWh.
The project cost £1.66m. With a total of 83 residents, that's about $25,000 per person. It would be interesting to compare this to the total investment needed for a typical non-renewable power infrastructure. This doesn't seem outrageously expensive, though (as the article mentions) this might be out of reach for communities in developing countries.
Yeah but the developing countries do not have that much of a power requirement. In India most villages would be fine with just the fans and lighting. 5 units (kWh) should be sufficient for the whole day for a household. I am not sure how much of £1.66m was on solar.
Actually a large part of rural India still uses 60/100W light bulbs (filament ones) instead of LEDs as they are much cheaper(1/15th). I took 75W ceiling fans + 100W for the bulbs ~ (75W20hrs + 60W10hrs)*3rooms. I agree this is still on the higher side as all fans won't be running all the time and would be zero during winters (~3 months).
If we look at Google Fiber and start applying that kind of costing model... Most of that money went to digging and laying the underground grid to every building. While not doing it underground would be cheaper, there's still going to be a big outlay in materials and time to run overhead line to every building.
Strikes me that the benefit is more likely to lie in seeing this as a small scale trial of running an entire community largely on renewables? The project cost is a rounding error in EU budget terms.
So their main generator is a standard hydro turbine, 100kW, and they have some wind/solar toys producing so little on average as to be just for show. And they suffer rationing and higher-than-normal prices.
Maybe you've missed that they're an island and this is the cheaper alternative to diesel? They've done this all with their own money, they're not a VC firm willing to make big investments "just for show".
That is far less then the bonuses received by some individual bankers who only received them because their banks were bailed out by taxpayers, in the EU and elsewhere, which I presume includes some of the inhabitants of Eigg.
Because egregious misuses of public funds don't get the attention they deserve.
How does a subsidy of £1.66 million for an investment which serves a whole community compare with a single payment for the personal consumption of an individual who belongs to a group whose acts have resulted in economic depression for the last 10 years?
Eh, that's not too bad considering the alternatives. I like the SMR concept, but sadly it's been very hard to find good cost estimates, the hardest one Akademik Lomonosov (still projected for ~$300M), but it's a barge with a pair of KLT-40, meanwhile mPower's been shuttered, etc…
Went in assuming it was almost all hydro, and no surprise.
~110kW hydro (a main generator at 100kW and two smaller ones at 5~6kW), 24kW worth of wind generally producing 12kW and 50kW worth of panels generally producing 5. Although they do note that the panels reach ~25% of rate (so ~12kW) in the summer months, when hydro would be at its lowest.
The "toys" are what would drive any new growth in the system and to make up for the extra heating needs in the winter months. If the island had a larger source of hydro or geothermal, this wouldn't be much of a story, but the single source by itself isn't enough to meet all of the needs or they wouldn't have bothered to put them in place.
Sounds like an interesting place, I loved Isle of Skye when I travelled that area. I think the article might be overselling the "leading the world in energy" angle though -- I too live on an island where > 98% of the energy is from renewable sources [1], and it has over a million people on it.
I don't mean to downplay this achievement, but I've always thought that renewable power, as it is today, isn't going to scale to meet global energy demand. One of the biggest issues is that it's nontrivial to store electrical energy. I think the holy grail for renewable power is farming algae for biodiesel. Essentially solar power, only we get out chemical energy in the form of gasoline instead of electricity. Burning that gasoline would be carbon neutral, since the carbon was taken from carbon dioxide in the air during photosynthesis. Gasoline is much easier and cheaper to store than electricity, we can use existing power infrastructure to burn it, and it makes the transition from fossil fuels to renewable power trivial. Plus the organism just needs sunlight and nutrients and it will self-replicate, so will be much cheaper than solar panels.
I think we're probably decades away from this being a reality. More research needs to be done, and we'll almost certainly need to genetically modify the algae to produce more butane/octane/etc.
That report is better than most but it relies on the assumptions that 1) the grid can route power nearly instantaneously from LA to NYC with very low losses and 2) on cuts in per person energy use by 30-50% (primarily by switching to electric cars). I see both of those assumptions being even less likely than 3) we cover 6240 square miles (5 Rhode Islands) with solar panels.
Considering this required £1.6m of subsidy (£20,000 per person) , only being able to hit 90% renewable, with loads of gotchas (like serious rationing)
If you scaled this out to the UK, it means it would cost £1.2trillion to reach 90% renewable electricity.
While there will be some economies of scale and you probably wouldn't use diesel for backup, the UK doesn't have enough hydro to do this model, so it's likely the £20,000 per person subsidy would actually be way higher.
I think people are really underestimating the capital required to get past 30-40% renewable. It starts getting seriously expensive once you get past the easy bit (wind + solar).
Govt seems very happy to agree to a 90% renewable target by 2050 (say). There doesn't seem to be any costing at all to see how we get there.
Easy to do when you've got a shit-ton of hydro, which is the case of Scotland (85% hydro, and pretty much the entire potential capacity is installed).
For instance Iceland is 100% electricity and 85% primary energy from renewables, not exactly hard when you've got massive amounts of geo and hydro (respectively 27% and 83% for electricity, 65% and 20% for primary energy). Good luck applying that to Belgium or Florida.
> That page also says it's been overtaken by wind power.
Which is true now but beware the trap of "installed capacity", as of Q3 2016 Scotland had 1600MW hydro and 5800MW wind installed (difference of 3.6x), but the 2015 production numbers were 5.8TWh hydro and 13.9TWh wind (difference of 2.4).
Well, Belgium and Florida are kind of ok. But what would you do with Poland, which has basically no wind, solar or hydro generation potential? Life's going to be hard for some countries.
Just get them to pay a carbon tax which can be used to pay for installing renewable in the places where it makes sense. It's a global problem, and it needs global solutions.
And if they do happen to figure out something that's cheaper than the carbon tax they're paying (maybe they can extract biogas from waste food, sewage or farm slurry or maybe they just super-insulate their homes to save fuel) then they have an immediate financial incentive to roll it out.
Florida's a pretty good candidate for solar as well. If tidal power ever takes off beyond proof of concept level, Florida (with its position near the Gulf Stream) is in a really good place for that, too.
There are definitely places which probably could never be 100% renewable, which is why transmission, storage, and grid management technology are important too.
Although hydro has been around for a while, and wind power is currently the cheapest renewable, most folk seem to think Solar PV is the dominant power of the future, so I think Florida aka "the Sunshine State" will do okay.
I went a couple of years ago and can highly recommend it for work retreats. Very peaceful, enthusiastic islanders, and a surprisingly good internet connection. (Transit comes from a nearby university, then fibre to the coast, then a microwave link to the island, then small microwave links for each house, IIRC.)
Here are some films somebody I went with made about the internet and the island shop:
I'm bothered that so many people on here see the rationing that these people do as such a bad thing. The easiest way to increase the percentage of renewable energy that you personally use is through cutting usage and limiting peak demand. The energy company you pay will always use their renewable generating capacity because the unit cost of that energy is 0 compared to >0 for fossil fuel power. If your electric company all of a sudden needed to generate 50% less power, they would cut fossil fuel plants first.
There's no heat! Except in the community hall and church. I went in wondering how they deal with that. They never say. Burning peat? Wood? Just staying cold? Its the most important part of the consumer energy equation. Here, at 5kW per household max, there's no way they can heat using electricity.
New Zealand has been 80% renewable for many years (at least for electricity). We do have a great mix of geothermal and hydro but it can definitely be done at a country wide scale.
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[ 3.3 ms ] story [ 139 ms ] threadhttps://en.wikipedia.org/wiki/An_Sg%C3%B9rr_(Eigg)
That seems like a dystopia.
Signaling conservation requests isn't dystopian.
I think it is a victory if the community can work together to use less power when there is less supply rather then people using as much as they want and forcing rolling blackouts.
Sometimes, we ration equal amounts, based per person.
Sometimes, we ration unequal amounts, based on how many dollars/denars/quatloos each person is willing to pay.
Sometimes, we ration unequal amounts, by asking people who don't really need a good to voluntarily stop consuming it.
There are pros and cons to each system - but all of them are rationing systems.
One of these is not like the others.
This should be mentioned in the opening paragraph.
Net contributors to the EU, like the UK. We gave the EU more than they spent on us (of course, because there are poorer European countries).
You make it sound like you think EU funding money was a gift from other people. It was them doing us the favour of giving us some of our own money back.
If we choose to, we can spend exactly the same money in exactly the same way. Or we could democratically decide amongst ourselves to do something different with it.
> would not get 1.66M GBP from the UK government
They did get 1.66M from the UK government. It just went involuntarily via the middleman of the EU.
However don't try to make it like this is my single pro-EU issue. This is just one small example of a thing I like.
The EU is democratically representative too, in a very similar way to the UK parliament. They have the same shortfalls. It just happens that across the EU there is more support for solving the energy crisis than there is in UK Conservative government. In part that's because IMO the EU looks more long term whilst the UK government appears only to be concerned about getting through the next one election. In part it's because the liberal and green elements that aren't properly represented in the UK, because we lack proportional representation, don't get to pressure our government locally but do get to represent the demos in the EU. It's the EU's better, ie more representative, democracy that causes the leap-frogging.
>They did get 1.66M from the UK government. //
Not really, sure the UK provided their part share of that, but they were forced to by the elected EU layer of government. The major share came from the other EU countries. Germany pays around twice the contribution of the UK and with France, Italy, and Spain we pay about 50% of the contribution. So the money is about 0.83M from these 5, perhaps about 0.2M from the UK government.
>involuntarily via the middleman //
The UK voluntarily, through a democratic process, joined the EU. The nation chose to put itself in the position where it would contribute the 0.2M and the other countries would add their 1.5M to enable projects such as this all across Europe.
The EU has given funding to areas that the UK government has neglected for years. Why are they going to start giving the money to them now?
Free download: http://withouthotair.com
About the author:
David MacKay FRS is the Regius Professor of Engineering at the University of Cambridge. He studied Natural Sciences at Cambridge and then obtained his PhD in Computation and Neural Systems at the California Institute of Technology. He returned to Cambridge as a Royal Society research fellow at Darwin College. He is internationally known for his research in machine learning, information theory, and communication systems, including the invention of Dasher, a software interface that enables efficient communication in any language with any muscle. He was appointed a Lecturer in the Department of Physics at Cambridge in 1995 and was a Professor in the Department of Physics from 2003 to 2013. Since 2005, he has devoted much of his time to public teaching about energy. He is a Fellow of the Royal Society.
Nine months after the publication of 'Sustainable Energy - without the hot air', David MacKay was appointed Chief Scientific Advisor to the Department of Energy and Climate Change.
TED talk: https://www.youtube.com/watch?v=E0W1ZZYIV8o
Harvard talk: https://www.youtube.com/watch?v=GFosQtEqzSE
Update: I had no idea he had passed, such a loss.
I've bookmarked your page - I'll pay you a visit in Autumn!
Does it turn off when the radiator's cold though? Seems senseless to have it running 24/7, and annoying to turn it on/off all the time.
Yes it would increase electronic waste, that's far from a deal breaker for most people.
FWIW some dish-washers have a built in fan eg "TurboHeat Dry" on Kenmore.
You'd need to run a air blower into the same plumbing to make it do anything, and you'd need a fair bit of air to produce the same thrust.
I've been looking at radiator efficiency and last time I removed a radiator when decorating considered adding the foil backing to the wall but indications were that the cost of the foil in resources outweighed the benefit over something like a 10 year period, which surprised me.
Radiators have always bothered me since high-school physics in that the rhetoric that radiators are placed under windows to increase convection and circulate hot air never seemed quite to fit for me. It always _seems_ to be sending heat out the window.
In practice - referencing your https://cdn.shopify.com/s/files/1/0195/5444/t/45/assets/proc... image - what is supposed to happen is that the cold air is drawn in to the bottom of the radiator, rises over it, passes up and moves across the ceiling, falling as it cools and then being drawn back to the radiator.
Do you have any independent corroboration that radfan improves heating efficiency, or when used increases apparent warmth for the same cost of heating? I see you don't claim efficiency gains on the page but only appear to claim for "better" distribution of the warm air .. warmer air still rises though, right. But in the video you say "warmer home or your money back" which suggests you've proven it makes efficiency gains??
Good idea, would like to see some scientific work on the efficacy though before I'd commit to buy.
Now that we have double glazing the latter doesn't happen and the circulating convection current that the former is supposed to set up never really materialises as most rooms have obstructions that stop the full circulation of warm air and simply cause the warm air to rise to the ceiling and stay there (we've seen 10degC floor to ceiling temperature differences but the typical is around 4/5 degC).
The Radfan helps set up that warm air circulation/cyclic convection current by essentially giving the radiator a little top up to get the air moving. It also reduces heat loss through the window by about 35% by diverting the flow of air away from the window a bit.
The testing we have done is twofold, field trials with 10 housing associations to see what the behavioral impact is but more importantly we have had controlled and independent testing carried out by the Salford University Energy House (http://www.salford.ac.uk/research/best/research-groups/appli...) that corroborated our own in house testing that showed the Radfan acted as a destratifier (temperature at the ceiling decreased and the temperature at sofa height increased by the same amount), reduced the heat lost through the window, allowed the central heating to turn off sooner (providing a small energy saving that more than offsets the running cost) and most importantly didn't introduce any forced convection on the radiator so the central heating wasn't working harder as there was no extra energy being extracted from the radiator (just a redistribution of the thermal energy already in the room).
The data shows that a Radfan will typically decrease the temperature at the ceiling by 1 to 2 degC and increase the temperature at the vertical mid point by a corresponding amount. It varies from home to home and in a very small percentage (less than 0.5%) it has minimal impact, hence we offer the warmer home guarantee so that if a home is in that small 0.5% (which we are unable to define as homes vary so much) then you can return for a full refund - we only want people living with a Radfan if they feel the benefit.
This page summarises our independant test results: https://www.radfan.com/pages/energy-saving
Fuzzy pictures from my trip here; the first few are from Mallaig, the other end of the ferry link:
https://goo.gl/photos/GQNcBpE4vVgv1A1i7
e.g. in Applecross on the mainland nearby, they're just finishing installation of a community-funded hydro system. It'll produce 90kW, with an income of about 100k GBP a year going towards the community and small shareholders: http://www.applecrosshydro.scot/
90kW is a toy, though. It's not going to provide energy independence for anyone. Rather more significant is the estate across the loch from my father's village, which is installing 3.5MW of private hydroelectricity: http://www.hydroworld.com/articles/2016/06/gilkes-begins-con...
But a 3.5MW plant, if we assume it runs at 100% capacity for a year, is going to produce 0.02TWh of energy, which is about 2 ktoe (kilotons of oil equivalent). In 2015 the UK used 140000 ktoe, of which only about 20000 ktoe are electricity. (https://www.gov.uk/government/uploads/system/uploads/attachm...)
These systems are important locally, but they're not going to run cities.
Edit: misread one of the graphs, corrected the number above. (The stupid graphs all have lines in slightly different shades of bodily function. Maybe they were trying to make a point.)
No, that's the big mostly offshore wind farms. Currently sitting at 12% of demand: http://gridwatch.templar.co.uk/
Energy independence on the personal level is as much of a pipe dream as economic independence. You might be able to achieve it at great expense, but what for? Even on Eigg the islanders are on a little grid.
...but I do need to point out that 12% of electrical demand is about 1800 ktoe, which is only about 1% of total energy demand. We use about six times more petroleum energy that all electrical demand put together.
Scotland already went through a period of energy resource shortage in the 1800s when there were very few trees left. Going back to only locally renewable resources might be like that again.
Tide is one of the few renewable technologies that generates reliable power, and so is suitable for baseline load. Even in Scotland, the wind drops. But it's had very little investment, partly because of a poor reputation from horrific ecological damage caused by tidal barrages in the past, but mostly because wind is sexier.
But plants big enough to actually make a difference are going to be very, very big. Microgeneration is great for small rural communities, but we live in cities these days.
Here's a new 320MW tidal lagoon being built in Wales: http://www.tidallagoonpower.com/projects/swansea-bay/ These only work when attached to a coastline, though.
Can I pick your brains about MSP430FR5994 UART code in assembler at some point please?
TIA
No, but then there's only 83 people to distribute the costs over as well, and a consequent lack of economies of scale.
For instance, from the article, they have four wind turbines, each 6 kW; I'm sure the multi-MW wind turbines used in larger wind parks produce power at a significantly lower price/kWh.
That almost went very Wicker Man
This seems like a design anti-pattern.
perhaps that explains the desirability of "for show" elements
How does a subsidy of £1.66 million for an investment which serves a whole community compare with a single payment for the personal consumption of an individual who belongs to a group whose acts have resulted in economic depression for the last 10 years?
It just seems like agenda pushing.
~110kW hydro (a main generator at 100kW and two smaller ones at 5~6kW), 24kW worth of wind generally producing 12kW and 50kW worth of panels generally producing 5. Although they do note that the panels reach ~25% of rate (so ~12kW) in the summer months, when hydro would be at its lowest.
[1] https://en.wikipedia.org/wiki/South_Island#Energy
I think we're probably decades away from this being a reality. More research needs to be done, and we'll almost certainly need to genetically modify the algae to produce more butane/octane/etc.
There are non trivial problems to solve, but the core set of technologies already exist or are experiencing Moore's law like cost curves.
https://web.stanford.edu/group/efmh/jacobson/Articles/I/USSt...
If you scaled this out to the UK, it means it would cost £1.2trillion to reach 90% renewable electricity.
While there will be some economies of scale and you probably wouldn't use diesel for backup, the UK doesn't have enough hydro to do this model, so it's likely the £20,000 per person subsidy would actually be way higher.
I think people are really underestimating the capital required to get past 30-40% renewable. It starts getting seriously expensive once you get past the easy bit (wind + solar).
Govt seems very happy to agree to a 90% renewable target by 2050 (say). There doesn't seem to be any costing at all to see how we get there.
For instance Iceland is 100% electricity and 85% primary energy from renewables, not exactly hard when you've got massive amounts of geo and hydro (respectively 27% and 83% for electricity, 65% and 20% for primary energy). Good luck applying that to Belgium or Florida.
Both Belgium and Florida seem like good candidates for offshore wind, although I'd be worried about hurricanes in Florida.
> That page also says it's been overtaken by wind power.
Which is true now but beware the trap of "installed capacity", as of Q3 2016 Scotland had 1600MW hydro and 5800MW wind installed (difference of 3.6x), but the 2015 production numbers were 5.8TWh hydro and 13.9TWh wind (difference of 2.4).
And if they do happen to figure out something that's cheaper than the carbon tax they're paying (maybe they can extract biogas from waste food, sewage or farm slurry or maybe they just super-insulate their homes to save fuel) then they have an immediate financial incentive to roll it out.
There are definitely places which probably could never be 100% renewable, which is why transmission, storage, and grid management technology are important too.
https://en.wikipedia.org/wiki/Renewable_energy_in_Iceland
Here are some films somebody I went with made about the internet and the island shop:
http://text.louisedowne.com/post/relative-economies-of-scale http://text.louisedowne.com/post/relative-economies-of-scale...