25 ms·

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

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: https://goo.gl/photos/GQNcBpE4vVgv1A1i7 https://goo.gl/photos/GQNcBpE4vVgv1A1i7

david-given 10y ago
...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/ 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-construction-of-three-small-hydroelectric-plants-in-scotland.html 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/attachment_data/file/573269/ECUK_November_2016.pdf 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.)
- pjc50 10y ago
  > not going to run cities No, that's the big mostly offshore wind farms. Currently sitting at 12% of demand: http://gridwatch.templar.co.uk/ 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.
  - david-given 10y ago
    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.
    - ZeroGravitas 10y ago
      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.
    - pjc50 10y ago
      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.
      - david-given 10y ago
        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. Here's a new 320MW tidal lagoon being built in Wales: http://www.tidallagoonpower.com/projects/swansea-bay/ http://www.tidallagoonpower.com/projects/swansea-bay/ These only work when attached to a coastline, though.
- monsonite 10y ago
  David, Can I pick your brains about MSP430FR5994 UART code in assembler at some point please? TIA
jabl 10y ago
> 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.
oliyoung 10y ago
> At one point I was kidnapped and taken to their community nativity play That almost went very Wicker Man

david-given 10y ago

...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/ 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-construction-of-three-small-hydroelectric-plants-in-scotland.html 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/attachment_data/file/573269/ECUK_November_2016.pdf 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.)

pjc50 10y ago
> not going to run cities No, that's the big mostly offshore wind farms. Currently sitting at 12% of demand: http://gridwatch.templar.co.uk/ 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.
- david-given 10y ago
  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.
  - ZeroGravitas 10y ago
    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.
  - pjc50 10y ago
    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.
    - david-given 10y ago
      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. Here's a new 320MW tidal lagoon being built in Wales: http://www.tidallagoonpower.com/projects/swansea-bay/ http://www.tidallagoonpower.com/projects/swansea-bay/ These only work when attached to a coastline, though.
monsonite 10y ago
David, Can I pick your brains about MSP430FR5994 UART code in assembler at some point please? TIA

jabl 10y ago

> 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.

oliyoung 10y ago

> At one point I was kidnapped and taken to their community nativity play That almost went very Wicker Man