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  1. 25 Nov '15 08:34 / 3 edits
    http://phys.org/news/2015-11-solar-energy-underground-cloudy-day.html
    "...Over the last few years, Mark Jacobson, a Stanford professor of civil and environmental engineering, and his colleague, Mark Delucchi of the University of California, Berkeley, have produced a series of plans, based on huge amounts of data churned through computer models, showing how each state in America could shift from fossil fuel to entirely renewable energy.

    In a new study published today in Proceedings of the National Academy of Sciences, they use the data from those single-state calculations of the number of wind, water and solar generators potentially needed in each state to show that these installations can theoretically result in a reliable, affordable national grid when the generators are combined with inexpensive storage and "demand response" – a program in which utilities give customers incentives to control times of peak demand.

    The proposed system relies on the ability to store and retrieve heat, cold and electricity in order to meet demand at all times.

    Summer heat gathered in rooftop solar collectors could be stored in soil or rocks and used for heating homes in winter. Excess or low-cost electricity could be used to make ice, which would be used for later cooling when the price of electricity is high.

    Excess electricity could also used to make more electricity, by supplementing the energy-producing mechanisms that drive concentrated solar power plants and pumped hydroelectric facilities. Utilities would also provide incentives to reduce energy use during times of peak demand.
    ..."

    This is a case of "where there is a will, there is a way". In this case, a way to cost-effectively go all-renewable.

    Unfortunately, the link then goes on to speak of using some hydrogen storage power, which, except possibly for some aircraft because there the energy density is of critical importance, I always think is a very insidiously deeply flawed strategy.
  2. 25 Nov '15 12:09
    Originally posted by humy
    http://phys.org/news/2015-11-solar-energy-underground-cloudy-day.html
    "...Over the last few years, Mark Jacobson, a Stanford professor of civil and environmental engineering, and his colleague, Mark Delucchi of the University of California, Berkeley, have produced a series of plans, based on huge amounts of data churned through computer models, showing how eac ...[text shortened]... density is of critical importance, I always think is a very insidiously deeply flawed strategy.
    It's possible to go entirely 'renewable', but it's much easier to go renewable+nuclear.

    You get the same zero emissions benefits, without the need for users to restrict their usage
    at peak times to avoid over-stressing the grid.

    It is of course possible to build heat storage and management systems that store heat and cold
    to maintain our homes/offices/etc at pleasant temps all year round.
    And new build with high insulation should absolutely be constructed [and be required to be
    constructed] with those capabilities.
    It's a whole other kettle of fish when you are talking about retrofitting the existing housing stock
    of tens/hundreds of millions of badly insulated homes that were never designed for this kind of
    technology. It's very disruptive and expensive to add on such technology after the fact.
    I know, because I've looked into trying to convert my 60's built home. It's prohibitively expensive/impossible
    to make this house properly efficient. It would be easier to knock it down and start again from scratch.
    Multiply that by millions and you have a huge headache.
    I am constantly appalled that new builds are not required to have such features as 'rain water capture' and
    'contraflow heat exchangers' and 'solar thermal/geothermal' and other heat management/storage systems
    as standard. Because these features make the house nicer to live in AND more environmentally sound and
    they are hugely expensive to retrofit, but not very expensive to build in from the start.

    Done properly, Nuclear power is cheep, clean, and sustainable. And it provides the kind of solid base load
    that makes running power grids [and our civilisation] easier and simpler.
    It irritates me no end that almost all environmentalists irrationally rule it out and then try to solve our energy
    problems with one hand tied behind their backs.

    It's possible, but there is a faster and simpler solution available.
  3. Standard member sonhouse
    Fast and Curious
    25 Nov '15 12:25
    Originally posted by googlefudge
    It's possible to go entirely 'renewable', but it's much easier to go renewable+nuclear.

    You get the same zero emissions benefits, without the need for users to restrict their usage
    at peak times to avoid over-stressing the grid.

    It is of course possible to build heat storage and management systems that store heat and cold
    to maintain our homes/ ...[text shortened]... tied behind their backs.

    It's possible, but there is a faster and simpler solution available.
    Nuclear is certain, however the downsides are considerable. Look at Chernobyl or 3 mile Island. And you have to find a REALLY deep hole to deposit that 100,000 year half life leftovers. Fortunately the big accidents like Fukashima are few and far between but when they happen and they WILL happen somewhere sometime, they are really big disasters.

    I see Fission reactors as only a stopgap till fusion reactors come online commercially.

    Whether that will be the Z pinch, laser inertial, tokamak's like ITER, whoever wins out, the waste products will be far easier to handle which is not to say those waste products will be totally benign, they won't be, but for one thing, fusion is way more powerful pound for pound than fission so there will be less bad stuff from day one and there won't be the super high AMU stuff of Fission to deal with, all in all a much better deal than fission any day.

    Now if the scientists and engineers will just get off their deadbeat asses and do it!
  4. 25 Nov '15 12:54
    Originally posted by sonhouse
    Nuclear is certain, however the downsides are considerable. Look at Chernobyl or 3 mile Island. And you have to find a REALLY deep hole to deposit that 100,000 year half life leftovers. Fortunately the big accidents like Fukashima are few and far between but when they happen and they WILL happen somewhere sometime, they are really big disasters.

    I see Fi ...[text shortened]... y day.

    Now if the scientists and engineers will just get off their deadbeat asses and do it!
    Nuclear is certain, however the downsides are considerable. Look at Chernobyl or 3 mile Island. And you have to find a REALLY deep hole to deposit that 100,000 year half life leftovers. Fortunately the big accidents like Fukashima are few and far between but when they happen and they WILL happen somewhere sometime, they are really big disasters.


    First off, let's compare like with like. Chernobyl, and all the early nuclear accidents where on rushed cold war
    early reactors who's main purpose was to make nuclear weapons materiel as fast as possible.
    Chernobyl's 'containment building' was a [I kid you not] corrugated iron shack. I've seen garden sheds with more
    structural integrity. It is not fair to judge a modern day reactor by those early cobbled together prototypes built
    in a rash with no more than a cursory glance towards safety.

    If you leave out those 'disasters waiting to happen nuclear barbecues', and instead look at the next generation of
    civil power plants... You have only two serious incidents.

    3 Mile Island [3MI], and Fukashima. [FKA]

    In the 3MI incident nuclear materiel was spilled into the containment building. There was no serious contamination
    outside the containment building, and the only real fallout was political.

    In the FKA incident, radioactive materials were released into the environment. However the total number of expected
    deaths [beyond the few workers hurt by explosions] above background from the fallout is in single digits over the next
    50 years. IE, so small we cannot detect it even with statistical methods.

    And a relatively small area is contaminated above what is probably safe for a number of decades.


    In other words, current nuclear power is many orders of magnitude safer when it fails catastrophically than fossil fuel
    generation is when working as intended.


    And moreover, next gen nuclear reactors, those using molten salt technology in one form or another are not
    pressurised and cannot sustain a runaway reaction or explode.

    If you get a crack in the pressure vessel in a High Pressure Water Reactor, or a Gas Core Reactor, and you have
    a major problem as hot corrosive radioactive coolant gas leeks out.

    If you get a crack in a molten salt containment vessel [which is much less likely as it's not under pressure] then
    at worst, the molten salt slowly leaks out onto the floor where it just puddles and cools.
    If the reactor is in a cold room [ie not at hundreds of degrees C] then the salt freezes and plugs the leak.
    It's self sealing.

    We have built working reactors that use this technology, and can do so again.

    We can mass produce these reactors today, not in 30~40 years like fusion reactors.
  5. 25 Nov '15 12:55
    Originally posted by sonhouse
    Now if the scientists and engineers will just get off their deadbeat asses and do it!
    The hold-ups are all political.
  6. 25 Nov '15 15:50
    Of course the reality is that many current power plants will not be shut down any time soon. We should stop worrying about the intermittency of solar and wind until it actually presents a problem. The reality is that if we decide to go renewable it will take many years to actually build all the solar and wind farms and for a very long time the internmittency problem will simply not exist. Only when solar and wind are producing the bulk of the power is it an issue. Meanwhile hydro is going nowhere and can provide some baseload, and if Germany is anything to go by biogas will play a major role in renewables anyway and that does not suffer from intermittency. And there are other options such as geothermal.
    Lets be honest, the whole intermittency issue largely false criticism cooked up by the fossil fuel industry.
  7. 25 Nov '15 15:59
    Originally posted by twhitehead
    Of course the reality is that many current power plants will not be shut down any time soon. We should stop worrying about the intermittency of solar and wind until it actually presents a problem. The reality is that if we decide to go renewable it will take many years to actually build all the solar and wind farms and for a very long time the internmitte ...[text shortened]... st, the whole intermittency issue largely false criticism cooked up by the fossil fuel industry.
    It is an issue, not an unsolvable one, but it is an issue.

    And given that we now need very radical and fast change, IF we are to make those
    changes it WILL have to be taken into account.

    Any plan for how to go 100% green requires an end goal that is realistic.

    If you plan for a 100% renewables future, then your plan must include how you deal with
    this problem.

    If it doesn't, people will correctly point out that your plan is not viable, and you loose the argument.

    MY big problem is that this plan is for a carbon free future by 2050.

    You can build nuclear power plants in 10~15 years.

    You can thus, by using nuclear and renewables, achieve zero emissions by 2025~2030, if you
    were determined to do so.

    Given that my plan gives us more energy [and hence better quality of life] while using substantially less
    space [wind farms and solar arrays are much less attractive than empty countryside] and will do it faster,
    my plan is better.
  8. 25 Nov '15 16:12
    Originally posted by googlefudge
    And given that we now need very radical and fast change, IF we are to make those
    changes it WILL have to be taken into account.
    Yet you are still talking nuclear something we both know cannot undergo radical and fast change. New nuclear takes 10-20 years at best - and that's just for the first demonstration reactors.

    Any plan for how to go 100% green requires an end goal that is realistic.
    Then lets be realistic and look at just how long it takes to ramp up manufacturing of solar panels and wind turbines. There are limits.

    If you plan for a 100% renewables future, then your plan must include how you deal with
    this problem.

    In the long term I see renewables other than wind and solar resolving the problem. But at the present point in time and for a very long time to come, it is a non-issue.

    You can build nuclear power plants in 10~15 years.
    I think that is over optimistic for new nuclear. Are you talking about traditional nuclear?

    And if you are willing to invest that much why choose nuclear instead of renewables? Biogas and geothermal can easily provide sufficient baseload.
  9. Standard member sonhouse
    Fast and Curious
    25 Nov '15 17:23
    Originally posted by googlefudge
    [quote]Nuclear is certain, however the downsides are considerable. Look at Chernobyl or 3 mile Island. And you have to find a REALLY deep hole to deposit that 100,000 year half life leftovers. Fortunately the big accidents like Fukashima are few and far between but when they happen and they WILL happen somewhere sometime, they are really big disasters.[/ ...[text shortened]... so again.

    We can mass produce these reactors today, not in 30~40 years like fusion reactors.
    What about the time frame for building such reactors? The old ones at least are billion dollar plus items, what is the cost of the molten salt reactor? It seems to me you still have a nasty cleanup to do 30 years down the road when you decommission one, having to store fission products for thousands of years.

    The quest to renewables will always be a mix of technologies, we would never put all our eggs in one basket, say solar alone. One super volcano would wipe out all the energy for months. So you hedge your bets and rely on solar, wind, wave, hydro, nuclear and later on, fusion. Seems to me that is how it will happen.

    The main question is, will it stop climate change, are we already too late to stop the worse effects, since we are already seeing bad effect right now.
  10. 25 Nov '15 17:56
    Originally posted by sonhouse
    One super volcano would wipe out all the energy for months.
    Surely solar power would be the least of our worries in such an event?
  11. 25 Nov '15 19:27
    Originally posted by googlefudge
    It's possible to go entirely 'renewable', but it's much easier to go renewable+nuclear.

    You get the same zero emissions benefits, without the need for users to restrict their usage
    at peak times to avoid over-stressing the grid.

    .
    I started a thread in the debates forum over this issue entiteled "degrowth".

    In it I make the case for climate change merely being a means of restricting and controlling the populace. If so, nuclear simply won't do for the very reasons I stipulate. That is why climate change advocates are also against nuclear power.
  12. 25 Nov '15 23:45
    Originally posted by whodey
    I started a thread in the debates forum over this issue entiteled "degrowth".

    In it I make the case for climate change merely being a means of restricting and controlling the populace. If so, nuclear simply won't do for the very reasons I stipulate. That is why climate change advocates are also against nuclear power.
    No, what you make in that thread is a crazy conspiracy nut theory with no substance in reality.

    There are a whole bunch of reasons why large parts [but not all] of the green movement is against
    nuclear power. And that isn't one of them.

    Global warming, and associated climate change, is a recognised fact about the world. Denied only
    by crack-pot conspiracy nuts, and the fossil fuel industry [at-least publicly] and their lackeys.

    You are of the former variety of denier.

    You systematically deny reality, about this, and just about any other issue.
  13. 26 Nov '15 04:31
    Originally posted by googlefudge
    No, what you make in that thread is a crazy conspiracy nut theory with no substance in reality.

    There are a whole bunch of reasons why large parts [but not all] of the green movement is against
    nuclear power. And that isn't one of them.

    Global warming, and associated climate change, is a recognised fact about the world. Denied only
    by crack-pot ...[text shortened]... riety of denier.

    You systematically deny reality, about this, and just about any other issue.
    Nuts like you say that the world is being destroyed by global warming.

    How bad then could nuclear power be as a solution to your little problem since it gives off zero carbon emissions and on a mass scale? Huh?

    This is why I know people like you are full of it.
  14. 26 Nov '15 07:53
    Originally posted by whodey
    I started a thread in the debates forum over this issue entiteled "degrowth".

    In it I make the case for climate change merely being a means of restricting and controlling the populace. If so, nuclear simply won't do for the very reasons I stipulate. That is why climate change advocates are also against nuclear power.
    what the hell are you on?
    Do you just make up a conspiracy theory as you go along?
    What is the premises/evidence for this strange conspiracy theory?
  15. 26 Nov '15 08:12 / 7 edits
    Originally posted by whodey
    Nuts like you say that the world is being destroyed by global warming.

    How bad then could nuclear power be as a solution to your little problem since it gives off zero carbon emissions and on a mass scale? Huh?

    This is why I know people like you are full of it.
    Nuts like you say ...

    you mean people that, unlike you, are qualified scientists and actually see a problem you cannot see because they understand the physics while you don't?
    How bad then could nuclear power be as a solution to your little problem since it gives off zero carbon emissions and on a mass scale? Huh?

    I just like to point out that, if only you had been paying attention to our posts, you would have easily noticed that googlefudge (and occasionally a few others in other threads) has repeatedly spoken up in favour of nuclear power and in many threads.
    He had already rightly asserted in this thread that “It's possible to go entirely 'renewable', “ but then rightly or wrongly asserted immediately after that “...but it's much easier to go renewable+nuclear... “.

    I should also point out that I and many others here certainly wouldn't rule out nuclear as at the very least a possible partial solution to the problem and many of us scientists ARE seriously looking into it at least as a partial solution to global warming. It is just a matter of determining which is the most cost-effective solution that can be scaled up fast enough to do some good.


    ... and on a mass scale?

    It is currently simply not economically nor physically feasible for the world to go all-nuclear or even mainly nuclear within, say, the next 20 years. That would require an impractical stupendous scale-up of building of large numbers of nuclear power stations as well as a massive scale-up of mining and processing of Uranium and all that is just too unrealistic. A more practical and realistic proposal albeit not necessarily the best one, at least for now but not necessarily forever (because nuclear fusion will eventually become a viable option ), would be a fairly modest scale up of nuclear as a partial solution with renewables doing most of the rest.