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  1.  
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      CommentAuthorfostertom
    • CommentTimeApr 18th 2016 edited
     
    Posted By: jamesingramhttp://www.sciencealert.com/how-graphene-could-help-solar-panels-produce-energy-when-it-s-raining" >http://www.sciencealert.com/how-graphene-could-help-solar-panels-produce-energy-when-it-s-raining
    Well that's an idea
    A short while ago, it seemed (to me) that PV economies-of-scale had been largely reached and set-up costs had reduced to a plateau where they were likely to stay.

    Far from it, apparently - non-silicon (e.g. thin film/organic) PV panels on the way, new non-bright-sun sources being harnessed, economy-of-scale hardly begun. PV will shortly resume its up-front cost-downward trajectory, becoming as ubiquitous and affordable as mobile phones - and thereafter the marginal 'per kWh' cost of electicity production wil become (well, is already) near-zero.

    Centralised electicity producers won't begin to compete; the grid will still be needed for a while more; near-PH buildings will cost nothing to power; the non-PH existing buildings will become prohibitive if not impossible to power.
    • CommentAuthorEd Davies
    • CommentTimeApr 18th 2016 edited
     
    .
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      CommentAuthorfostertom
    • CommentTimeApr 18th 2016
     
    Then there's thermoelectric production from temperature difference e.g. waste heat - good enough for arctic explorers to power a glimmer from their cooking stove apparently. PV as presently understood was in that microvolt bracket to begin with. All worth intensive development.
    • CommentAuthorringi
    • CommentTimeApr 18th 2016
     
    Until the cost of storage becomes so cheap, that we can store all the power we need for weeks, generators will be needed. We will just have to pay the generators more for when they are not generating, as we need them as an insurance policy.
    • CommentAuthorEd Davies
    • CommentTimeApr 18th 2016 edited
     
    .
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      CommentAuthorfostertom
    • CommentTimeApr 18th 2016
     
    It's coming - that's clear too - won't be long.
    • CommentAuthorJamster
    • CommentTimeApr 18th 2016
     
    "And when we have nuclear power, it'll all be too cheap to meter!" Said someone sometime...
  2.  
    Ed is that your stuttering in paraplectic agony at FT in his joyous ecclesiastical soothsayer role or have you forgotten you can whisper any post, other than an OP, to yourself and it will disappear?
    •  
      CommentAuthorfostertom
    • CommentTimeApr 19th 2016
     
    That's a good one
    • CommentAuthorEd Davies
    • CommentTimeApr 19th 2016 edited
     
    Gotanewlife - I'm pointedly [¬Ļ] backing away from involvement in the conversation. But, yeah, ‚Äúparaplectic agony‚ÄĚ :confused:

    [¬Ļ] Pun intended.
    • CommentAuthorSimon Still
    • CommentTimeApr 19th 2016 edited
     
    Posted By: fostertom
    Posted By: jamesingramhttp://www.sciencealert.com/how-graphene-could-help-solar-panels-produce-energy-when-it-s-raining" >http://www.sciencealert.com/how-graphene-could-help-solar-panels-produce-energy-when-it-s-raining
    Well that's an idea

    Centralised electicity producers won't begin to compete; the grid will still be needed for a while more; near-PH buildings will cost nothing to power; the non-PH existing buildings will become prohibitive if not impossible to power.


    mmm-kay

    Remind me what the replacement rate for buildings in the UK is?
    And the %age of new buildings that are to passive standard?
    And the payback time for a rebuild of a house (or retrofit to passive standard) based on average UK household energy costs of £1,264 p.a. (you can add a loading factor of c10 to that if you want - make it £10k p.a. for simplicity).

    Then explain how self generation with individual household solar panels and batteries is going to work in areas of high population density. Such as:
    https://upload.wikimedia.org/wikipedia/commons/1/18/Hong_Kong_Night_Skyline.jpg
    or even just
    https://www.thebureauinvestigates.com/wp-content/uploads/2013/05/shutterstock_772862.jpg

    UK population (http://www.tradingeconomics.com/united-kingdom/rural-population-wb-data.html) is
    - 88.7% Urban
    - 26% in agglomerations of >1m

    Can you define "a while"?
    •  
      CommentAuthorfostertom
    • CommentTimeApr 19th 2016 edited
     
    Posted By: Simon Stillexplain how self generation with individual household solar panels and batteries is going to work in areas of high population density
    Are you ruling out multifold increases in kWh collected per m2 of collector? I wouldn't.

    Of course HK households couldn't power themselves given either:
    a) present kWh/m2 of collector (note - kWh not kW), and/or
    b) present heat demand for space heating (or a/c in HK's case) and/or
    c) present energy demand for other domestic purposes - lighting, fridges, water heating, appliances etc

    All of those will continue to change - even extra appliances outpacing efficiency improvements will eventually reverse. kWh potential per $ upfront and per m2 of collector will continue to improve vastly.

    The two curves will intersect, cross over, and put the centralised generators out of business. "A while"? what do you suggest?

    I was concentrating on b), in talkng about PH.
    Posted By: Simon Stillpayback time for a rebuild of a house (or retrofit to passive standard) based on average UK household energy costs of £1,264 p.a. (you can add a loading factor of c10 to that if you want - make it £10k p.a. for simplicity).
    You're saying major near-PH retrofit won't happen, by extrapolating all present factors as if they're not changing. c10 sounds generous but is greatly insufficient - we're talking exponentials here.

    In a near-ruined central generating industry, justifying no new investment, just running-down on old machinery (like today's oil industry), non-PH buildings would be one of its last customers. What will that say about the conomics of remaining non-PH? I say it'll be a steepening no-brain economic necessity to PH the entire stock.

    It's ironic that cheapening energy will be the incentive to PH the stock. That's because the whole autonomous zero-marginal-cost cheap-energy proposition only works given massive demand reduction.
    • CommentAuthorSimon Still
    • CommentTimeApr 19th 2016 edited
     
    and I think you're in the realms of fantasy and that it's dangerous to make these claims without actually providing the maths to back them up. Just waving your hands in the air saying "will eventually reverse", "exponential", "improve vastly" doesn't do it.


    Demand side - the big wins are already banked as far as i can see.
    - improvements in lighting are now marginal. The big gain was incandescent to LED
    - TV's have got bigger, offsetting nearly all of the gains from Tube to flat panel
    - cooking is resistive - no efficiency gains to be had (other that better insulation)
    - Fridges/Washing. Gains are now marginal

    You're in the same space as the futurists often unchallenged 'electric cars will solve congestion and pollution'. A road full of electric cars is just as congested as if they're diesel. Current power generation isn't clean so they just move the pollution elsewhere. Power currently 'generated' by fossil fuels in motor vehicles is roughly equivalent to our national electricity generation capacity so we either need to double the capacity or move all current demand.

    ie to actually eliminate the grid and current generation you need local generation at double current demand. More if you're adding water heating to it as well (assuming that's largely gas at present).

    I don't have time to do all the research to prove or disprove (but I'm not the one claiming any problems have been solved) but my instinct is that the numbers don't add up and that it's a *long* way off.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 19th 2016 edited
     
    • CommentAuthorbillt
    • CommentTimeApr 19th 2016
     
    Posted By: Simon Stilland I think you're in the realms of fantasy and that it's dangerous to make these claims without actually providing the maths to back them up. Just waving your hands in the air saying "will eventually reverse", "exponential", "improve vastly" doesn't do it.


    Quite right.

    PV collector efficiency is about 20% at the moment, theoretically 50% is possible, but even if you get to 100% collection is ultimately limited by the insolation and collector area. Small area, small power collected.

    kWhr harvested is directly linked to kWpk of the collector; to try to separate them is either disingenuous or demonstrates lack of knowledge.

    You don't need PH standards of insulation to dramatically reduce heating energy demand, just go back to 1950s levels of heating. People wore thick clothes and didn't heat most of the house at all.

    If we go back to the 50s in other respects (no electronic devices except for a wireless, no internet, no domestic freezers etc) we could cut electricity demand significantly. Good luck, trying to do that without draconian interventions.
    • CommentAuthorSimon Still
    • CommentTimeApr 19th 2016 edited
     
    The Zero Marginal Cost Society looks interesting. Will add to my reading list.

    However, a quick check of the lowest rated reviews on Amazon tallies with my criticism of your claims above -

    "The one big idea in the book, that the internet of things and associated technology will enable humans to increase the efficiency of their energy use from 13% towards 40%, is both madly optimistic and completely unjustified by any evidence or calculations."

    "brimming with fantastical claims about the future that have no research to back them up and mundane facts carefully referenced"
  3.  
    https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/449134/ECUK_Chapter_3_-_Domestic_factsheet.pdf


    Domestic electricity consumption, appliance efficiency etc etc.

    Interesting charts - freezers/fridges have got a lot better. Add insulation, better heat exchangers etc and you can make quite dramatic improvements. Levelling off now though.

    Wet appliances the savings aren't so great - washing machines use less water, more agitation, more soaking but you can only go so low and you still need to heat the water. Which of course explains the exhortations to wash at lower temperatures - behaviour will trump tech on washing.
    • CommentAuthorringi
    • CommentTimeApr 19th 2016
     
    There are now small fuel cells giving 50% efficiency from mains gas to electric, use the waist heat for DHW and space heating….

    Then use the unpredictable renewable to make gas to put into the mains gas storage system. It is a lot cheaper to store gas then electric. If wind come down to 1/10 of its current cost, the above maybe cheaper then shipping liquid gas round the world.

    The price of gas will go up, as soon as we start using less oil (due to electric cars etc), as at present as lot of gas production if a by-product of oil production.
  4.  
    it rains at night as well ;-)
  5.  
    This is why energy storage is the holy grail...

    Renewables have the capacity to provide more than eneough of our energy needs in its various forms. the problem is accumulation and storage of that energy on a local as well as national level.

    as for electric cars, when they run on petrol they can only run on ... petrol. When they are electric they can be run on what ever energy was used to generate that electricity. there is a clear advantage.
    •  
      CommentAuthordjh
    • CommentTimeApr 19th 2016
     
    Posted By: bot de pailleas for electric cars, when they run on petrol they can only run on ... petrol.

    Not true even today. Most cars can be converted easily to use LPG or compressed gas. There are also car engines available that run either on petrol or on stored compressed air. Production of methane and methanol from electricity is also practical although not yet economically sensible. The most pernicious downside of combustion engines is their emissions. That is where an electric motor scores, IF the electricity is clean.
  6.  
    Tangents....

    Tom was claiming new advances in renewables, notably increased efficiency/lower cost of solar and battery storage would lead to wholesale shift to passive housing and the collapse of the current energy generation companies/end of the grid. Seemingly on a fairly rapid, though unspecified, timescale.

    Which seemed pretty far fetched to me. A shift from fossil fuels for personal transport (which is certainly desirable) will vastly increase electrical demand, theres as yet no evidence of personal consumption actually falling significantly despite increases in efficiency of individual appliances and there are huge challenges to solar geneation and storage in urban areas (availability of suitable roof space, space for batteries etc etc).
  7.  
    But wont most cars be charged during the night when power stations are at idle?

    Also, electric car development will boost battery technology development. Energy storage is key both for generators and consumers. Night and day tariffs will become obsolete.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 19th 2016 edited
     
    Lots and lots to comment on here - great! Where to begin?

    Posted By: Simon StillA shift from fossil fuels for personal transport (which is certainly desirable) will vastly increase electrical demand
    Again, just extrapolating the present:

    Cars and buses - not just going electric,
    also super-lightweighting via carbon fibre etc, which has square-law effect on energy required.
    Indeed - power-of-perhaps-two-and-a-half effect, because with lower power, 4WD motor-in-wheel + regen braking becomes feasible, eliminating engine bay, gearbox/diff, driveshafts, the volume and weight of all those hence lighter body ... There's no reason why our personal transportation devices should weigh more than a Sinclair C5!
    Then self-driving cars-as-a-service eliminating much human-mood-created power-consuming acceleration/braking ... of course rent something bigger to transport stuff, or multiple kids, and as for long fast journeys ...

    Trucks - super-lightweighting not so significant, as long as payload continues to dwarf deadweight - but air-miles food and far-off sweatshop labour as robot-substitute are very recent fads which are already obsolete; on-the-spot manufacturing and re-localisation generally are in sight, vastly reducing ton-miles globally.
    • CommentAuthorSimon Still
    • CommentTimeApr 20th 2016 edited
     
    <blockquote><cite>Posted By: fostertom</cite>Cars and buses - not just going electric,
    also super-lightweighting via carbon fibre etc, which has square-law effect on energy required.
    Indeed - power-of-perhaps-two-and-a-half effect, because with lower power, 4WD motor-in-wheel + regen braking becomes feasible, eliminating engine bay, gearbox/diff, driveshafts, the volume and weight of all those hence lighter body .</blockquote>

    I do admire your enthusiasm and actually don't like being negative. I know that's hard to believe.

    I've sat in a Tesla (they've a 'showroom' in the Westfield shopping mall in West London). The Tesla model S is built on a lightweight aluminium space frame, has lightweight aluminium body panels and has all the space saving benefits you list. Inside feels huge with a completely flat floor. It's just as you describe with all that heavy mechanical stuff removed.

    However, batteries to give a 200km range, and the under armour to stop the batteries turning into a high speed bomb (https://www.youtube.com/watch?v=pYPr_z6BxA0 ) add a little weight. In fact it ends up weighing in at c2000kg, the same as a BMW 5 series. http://www.teslarati.com/tesla-model-s-weight/

    Yes, for most journeys the equivalent of an electric golf caddy would be sufficient. 85% of UK commuter car journeys are single occupancy so could be done in something smaller than a Smart car with people renting something bigger to transport stuff, or multiple kids. For longer journeys there are these fantastic, fast, self driving comfortable things called trains.The answer for in-city personal transport is the bicycle - it doesn't need technology, just a reallocation of road space.

    These aren't technological problems - the solutions already exist to get 80% there without any extra tech - but the barriers are political and emotional. Just look at the backlash against a small scheme that proposes to remove a nasty multi lane gyratory and prevent rat running through one of London's parks at peak times (but still allow it the rest of the day and still allow cars in the park all the time). This is at a location in Zone 1 London that's a 2 stop tube journey from Oxford Street. http://www.cs11.london/

    There's some wonderful technology in the pipeline but it alone doesn't solve the worlds problems - those challlenges are largely human.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 20th 2016
     
    Posted By: Simon Stillthose challlenges are largely human
    true - and therefore subject to overnight inversion, whether by old fashioned popular revolution, or by film, book, news event that floods the media. Just to look back 50, 10, even 1 yrear, is to see fantastic changes in general (not just fringe/greenie) awareness, not just national or even western, but worldwide.
  8.  
    <blockquote><cite>Posted By: bot de paille</cite>But wont most cars be charged during the night when power stations are at idle?

    Also, electric car development will boost battery technology development. Energy storage is key both for generators and consumers. Night and day tariffs will become obsolete.</blockquote>

    Biogas is being pushed in Germany with support from companies like Audi.

    Initially from farm production with injection into the national grid

    http://marcogaz.org/downloads/EFG2010/2_Dr_Harald_von_Canstein.pdf

    But longer term companies like Sunfire are already injecting gas derived from excess green energy into the grid.
  9.  
  10.  
    Posted By: billt

    If we go back to the 50s in other respects (no electronic devices except for a wireless, no internet, no domestic freezers etc) we could cut electricity demand significantly. Good luck, trying to do that without draconian interventions.


    This is something I've been musing about for a couple of years. I'd love to have a crack at going back to 1950s level of electricity and gas usage for an average family of 4 (does anyone know where I can find the figures from?)

    Rather than actually live as though I'm in the 50s, I'd be looking at using modern technologies. With LED lighting instead of incandescent bulbs, with low energy televisions instead of CRT tubes (or even wireless radios), with an efficient gas boiler and IWI/Double glazing/air tightness instead of a gas fire and 'geyser' for hot water, etc. etc.

    It must be doable. Perhaps in stages, I'll got back in time thorugh the decades until I get to 1950s. I'd imagine I'm already in the 90s as I think national energy usage is already lower today than the 1990s?
   
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