Eigg – A small Scottish isle that runs on 90-95% renewable energy
bbc.com
bbc.com
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 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
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.
Yes it would increase electronic waste, that's far from a deal breaker for most people.
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.
I've bookmarked your page - I'll pay you a visit in Autumn!
Fuzzy pictures from my trip here; the first few are from Mallaig, the other end of the ferry link:
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
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.
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.
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.
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 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?
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...
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...
One of these is not like the others.
That seems like a dystopia.
Signaling conservation requests isn't dystopian.
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.
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.
This seems like a design anti-pattern.
perhaps that explains the desirability of "for show" elements
It just seems like agenda pushing.
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?
~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.