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anonymous

How To Save Energy Using A Smart Strip Power Strip - 0 views

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    How smart power strips work to save energy.
ian d

Ch 19 Page 115: Sustainable Energy - without the hot air - 0 views

  • a little adds up to a lot,” if all those “littles” are somehow focused into a single “lot” – for example, if one million people donate £10 to one accident- victim, then the victim receives £10 million. That’s a lot. But power is a very different thing. We all use power. So to achieve a “big difference” in total power consumption, you need almost everyone to make a “big” difference to their own power consumption.
  • by reducing our population
    • ian d
       
      I think it's important to note that on current trends the UK population and hence UK energy demands will grow by 10% by 2030 to 70 million. Source UK Government Statistics.
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    OK .. Here is the answer to my earlier quibble doubting the untruth of "every little bit helps" ...
tony curzon price

Ch 21 Page 146: Sustainable Energy - without the hot air - 0 views

  • A final impediment to rational discussion of combined heat and power is a myth that has grown up recently, that decentralizing a technology somehow makes it greener. So whereas big centralized fossil fuel power stations are “bad,” flocks of local micro-power stations are imbued with goodness. But if decentralization is actually a good idea then “small is beautiful” should be evident in the numbers. Decentralization should be able to stand on its own two feet. And what the numbers actually show is that centralized electricity generation has many benefits in both economic and energy terms. Only in large buildings is there any benefit to local generation, and usually that benefit is only about 10% or 20%.
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    "small is beautiful" ... "but big is efficient" --- a sad fact for environmentalism to come to terms with -- where physics just won't play the politics
William Sigmund

Ch 18 Page 105: Sustainable Energy - without the hot air - 0 views

  • Power consumption per capita, versus GDP per capita,
    • dave woolcock
       
      Countries with nice warm climates should need less energy
  • Figure 30.1 (p231)
    • dave woolcock
       
      gives me Object not found error
    • William Sigmund
       
      Chapter 30 is not ready yet. Apologies!
  • The only notable ex- ception to the rule “big GDP implies big power consumption” is Hong Kong.
    • dave woolcock
       
      How much motorway driving occurs in HK? Compact urbanised countries need less road-miles
tony curzon price

Energy group read, week 5. Heat, hydro and light (oD) - 0 views

  • We use about as much to heat and cool ourselves (in Britain) as we use to move around in our cars, while lighting uses onlu a graction of that energy - especially using low energy fluorescent bulbs or the new generation of LED lights. Hydro-electric power in Britain, however, even with generosity from the wet Highlands, will only deliver about one third of the small amount of energy we use to light ourselves. How unfortunate that such accidental power-concentrators as mountains and streams are not more plentiful, and not just, maybe, for the energy benefits.
tony curzon price

"Small is beautiful" ... "but big is efficient" in heating systems | open Democracy New... - 0 views

  • The average winter-time temperature in English homes in 1970 was 13C. Today, 50% more than that is usually thought of as just about tolerable. There are three strategies for reducing the carbon footprint of keeping warm: reduce the temperature difference between the inside and outside; reduce heat losses from inside to outside and increase the efficiency with which energy is transformed into heat. The first two seem obvious and cheap solutions. We hear a lot about "nudging" as a policy, and this seems an ideal area for clever devices to make people aware that they could be heating less and leaking less heat. David does not mention my own favourite long term solution here---a widespread move to small exoskeletons as a substitute to housing: we should be able to walk around with our temperature control close to our bodies and our living spaces open to the elements. David makes a powerful argument for heat pumps rather than Combined-Heat-and-Power plants, and slips in a big fault-line in eco-politics versus eco-engineering: energy transformation efficiency tends to rise as scale rises, whereas green politics loves to decentralise and make solutions small and local. This chapter is full of low-ish tech, labor-intensive investments that make energy-efficiency sense today. This is just what government policy should be stimulating our economies with today.
tony curzon price

Low Carbon Transport: Bicycles, trains, electric cars and nuclear ships | open Democrac... - 0 views

  • Electrify transport. There's not much to beat trains+bicycles, and any government looking for a Keynesian stimulus should find lots of infrastructure opportunities here. David MacKay comes down softly on the car---which shows great realism---and finds that electrification is the only real solution there. He debunks hydrogen as a good energy carrier. Flying is a really tough case---there is not much that can be done to reduce its energy intensity. (I was sitting in an easyjet plane the other day that tried to convince me of its greenery by saying: "Flying contributes less CO2 than driving to the atmosphere" ...). Batteries are the way to go---though just wait for the peak lithium scares. David has an interesting aside on nuclear ships. If we could make the (political) world safe for small-scale nuclear power, maybe there's more than ships that could benefit.
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    Electrify transport. There's not much to beat trains+bicycles, and any government looking for a Keynesian stimulus should find lots of infrastructure opportunities here. David MacKay comes down softly on the car---which shows great realism---and finds that electrification is the only real solution there. He debunks hydrogen as a good energy carrier. Flying is a really tough case---there is not much that can be done to reduce its energy intensity. (I was sitting in an easyjet plane the other day that tried to convince me of its greenery by saying: "Flying contributes less CO2 than driving to the atmosphere" ...). Batteries are the way to go---though just wait for the peak lithium scares. David has an interesting aside on nuclear ships. If we could make the (political) world safe for small-scale nuclear power, maybe there's more than ships that could benefit.
tony curzon price

Ch 19 Page 117: Sustainable Energy - without the hot air - 0 views

  • Second, to supplement solar-thermal heating, we electrify most heating of air and water in buildings using heat pumps, which are four times more efficient than ordinary electrical heaters. This electrification of heating further increases the amount of green electricity required. Third, we get all the green electricity from a mix of four sources: from our own renewables; perhaps from “clean coal;” perhaps from nuclear; and finally, and with great politeness, from other countries’ renewables. Among other countries’ renewables, solar power in deserts is the most plentiful option. As long as we can build peaceful international collabor- ations, solar power in other people’s deserts certainly has the technical potential to provide us, them, and everyone with 125 kWh per day per person.
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    The basic plan: electrify transport, electrify heating, generate electricity from UK renewables, clean coal, nuclear and imported solar from deserts. There.
Ché Duro

David MacKay FRS: Sustainable Energy - without the hot air: Errata - 0 views

  • The lion's share of the money is thus cleaning up military mess, not civilian-power mess.
    • Ché Duro
       
      Once again I cannot help but feel that MacKay is promoting nuclear power, in spite of his own numbers. Firstly, his own endnote indicates that this £2 bn/year for 25 years is 50% too low. Now he returns to the subject claiming that the 'lion's share' is for military clean up. This article (www.telegraph.co.uk/finance/newsbysector/utilities/2793052/Washington-Group-wins-Sellafield-clean-up-contract.html) indicates that while the majority of the total waste is military in origin, it accounts for only about 20% of the total cost.
tony curzon price

Cutting the vampire appliances | open Democracy News Analysis - 0 views

  • Many gadgets consume a surprising amount of power on standby. David cut his electricity consumption by half by making sure his "vampire appliances" were kept off. There are real savings available here. David and friends set up "ReadYourMeter.org" to try to encourage others to make this sort of saving. According to the International Energy Agency, standby power consumes a surprising8% of residential electricity.
tony curzon price

Ch 15 Page 89: Sustainable Energy - without the hot air - 0 views

  • As for a 500 ml water bottle made of PET (which weighs 25 g), the embodied energy is 0.7 kWh – just as bad as an aluminium can!
  • Computers Making a personal computer costs 1800 kWh of energy. So if you buy a new computer every two years, that corresponds to a power consumption of 2.5 kWh per day.
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    plastic bottles, cans and product life cycles
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    raw material and production costs of a computer - 2.5kwh/day
tony curzon price

Group Read. Energy without hot air. Wave and Food | open Democracy News Analysis - 0 views

  • In which we learn that to get by on wave power you need to be very very insular -- that is, have a small number of people per unit length of exposed coastline (sounds like a nice place to me, but the British Isles don't fit the description) -- and also that our food habits, especially for red-blooded carnivores with meat-eating pets -- amount to more than half our driving habit in energy. There is a real energy case to be made for vegetarianism (approximately twice as efficient) and even more for veganism (another doubling).
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    Chapters 12 and 13 - Wave and food.
tony curzon price

Ch 13 Page 77: Sustainable Energy - without the hot air - 0 views

  • Eating meat requires extra power because we have to feed the queue of animals lining up to be eaten by the human.
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    The _real_ reason that meat is so energy inefficient: all the time you have to keep animals alive and fed before they become edible meat.
tony curzon price

Ch 12 Page 74: Sustainable Energy - without the hot air - 0 views

  • While wave power may be useful for small commu- nities on remote islands, I suspect it can’t play a significant role in the solution to Britain’s sustainable energy problem.
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    Offshore wave needs high length of exposed coast epr person. Small islands might do OK, not a big, densely populates island like the UK.
tony curzon price

Ch 8 Page 56 Sustainable Energy - without the hot air - 0 views

  • Loch Sloy’s surface area is about 1.5 km2, so the hydroelectric facility itself has a per unit lake area of 11 W/m2. So the hillsides, aqueducts, and tunnels bringing water to Loch Sloy act like a 55-fold power concentrator.
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    Lovely piece of reasoning
tony curzon price

Sustainable Energy - without the hot air: Ch 2 Page 24 - 0 views

  • One kilowatt-hour per day is roughly the power you could get from one human servant. The number of kilowatt-hours per day you use is thus the effective number of servants you have working for you.
    • tony curzon price
       
      This speaks vividly to the social liberation made possible by the taming of energy!
anonymous

Sustainable Energy - without the hot air: Ch 1 Page 14 - 0 views

  • The UK has made it onto the winners’ podium. We may be only an average European country today, but in the table of historical emitters, per capita, we are second only to the USA.
    • anonymous
       
      Past polluting is a distraction: 125-year emissions estimates are debatable; the message is clear based on today's actual and forecast emissions; and it's hard to moralize about a time when nobody foresaw the consequences. Should we apologise to the world for Victorian factory smoke?
    • tony curzon price
       
      The point of view from China is this: "there was 400ppm of CO2 concentration to "safely" get to; the early birds to the party eat up 90% of the cake; they are asking us not to eat much of the remaining 10% on grounds of equity..." This is a powerful argument from fairness, it seems to me. The point is not that the best place to cut emmissions is China, but rather who should pay for the cut. Tony
anonymous

Ch 14 Page 86: Sustainable Energy - without the hot air - 0 views

  • It doesn’t require high-cost hardware, in contrast to solar photovoltaic power.
    • anonymous
       
      A low-tech, non-experimental system that can be rolled (or floated) out progressively - and produces the goods - looks very attractive.
tony curzon price

Ch 20 Page 133: Sustainable Energy - without the hot air - 0 views

  • there is no prospect of significant improvements in plane efficiency.
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    Long distance travel is a real carbon problem---nuclear powered ships?
tony curzon price

Energy efficiency of transport nodes - gr8 graph: Sustainable Energy - without the hot air - 0 views

  • Figure 20.23. Energy requirements of different forms of passenger transport. The vertical coordinate shows the energy consumption in kWh per 100 passenger-km. The horizontal coordinate indicates the speed of the transport. The “Car (1)” is an average UK car doing 33 miles per gallon with a single occupant. The “Bus” is the average performance of all London buses. The “Underground system” shows the performance of the whole London Underground system. The catamaran is a diesel-powered vessel. I’ve indicated on the left-hand side equivalent fuel efficiencies in passenger-miles per imperial gallon (p-mpg). Hollow point-styles show best-practice performance, assuming all seats of a vehicle are in use. Filled point-styles indicate actual performance of a vehicle in typical use. See also figure 15.8 (energy requirements of freight transport).
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    Beautiful graph of the energy efficiencies of different modes of transport. Bicycle and train make for such a good combination --- why not stick to that?
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