[HN Gopher] Can solar and wind power Britain? An update of David...
___________________________________________________________________
Can solar and wind power Britain? An update of David MacKay's
numbers
Author : ZeroGravitas
Score : 95 points
Date : 2023-11-05 14:33 UTC (8 hours ago)
(HTM) web link (www.sustainabilitybynumbers.com)
(TXT) w3m dump (www.sustainabilitybynumbers.com)
| RobinL wrote:
| Great post - I've been looking for a serious update to Mackay's
| numbers for ages.
|
| One thing in curious about: developments in fixed wind turbines
| tech mean they are economically viable in more locations (e.g.
| deeper water) so can cover more area.
|
| But how much more do they produce per square km of deployment
| than Mackay's estimates?
|
| In his book, he has a nice section explaining that bigger
| turbines have to be spaced out more, so whilst theyre cheaper,
| they don't produce as much more energy as the headline 'output
| per turbine' would naively suggest.
|
| But modern turbines are higher, so they presumably 'catch' more
| wind, and windspeeds are more consistent higher up. But I'm
| curious how big an effect this is.
| cycomanic wrote:
| I don't MacKays estimates but the cited study seems to assume a
| capacity factor of 50% for a 15 MW turbine.
|
| Average turbine capacity of turbines installed in 2021 was 7.4
| MW but all manufacturers seem to have 15+MW designs in the work
| [1]. So the projection is slightly optimistic IMO. The capacity
| factor seems slightly more optimistic at 50% as worldwide
| average seem to have fluctuated between 35 and 45% [2].
| Although other numbers are closer to 60% for the UK [3]
|
| [1] https://www.energy.gov/eere/wind/articles/offshore-wind-
| mark... [2] https://www.statista.com/statistics/1368679/global-
| offshore-... [3] https://windeurope.org/about-wind/daily-
| wind/capacity-factor...
| yodelshady wrote:
| Source [3] seems highly suspicious. There's ~24 GW of wind
| capacity in the UK, the vast majority offshore, and according
| to Elexon Portal (https://www.elexonportal.co.uk, a good
| public frontend at http://gridwatch.org.uk/), which gives
| realtime grid data, the maximum production was 10. So an
| average cap factor of 39% is, well sorry it's wrong.
|
| And time and time again renewables _always_ seems to take
| optimistic, if not ludicrous estimates.
|
| Mackay's papers is indeed 15 years old, and what do we have
| now? _Extremely_ expensive power, backed by fossil gas,
| because if wasn 't, _people would die_. Avoiding 2 deg C and
| ecosystem collapse is not even vaguely possible anymore. In
| that time, 40 years ago, France got to 17 g / kWh. That's
| not a success and, for the literal trillions of ESG money
| spent, someone should be held accountable for that.
| coob wrote:
| I thought the issue with wind in the UK was that its supply is
| (Scotland) where the demand isn't (the south). So we'd (a) have
| to build loads of pylons or expensive underground cables and (b)
| lose a lot in transmission.
| nradov wrote:
| That's part of it, but storage for base load is still a more
| significant issue.
| ebiester wrote:
| Considering the length of transmission lines in the US, is 500
| miles (or so) the constraining factor with transmission?
| bluGill wrote:
| For AC. More than that and the ends start to be in different
| phases of the cycle and so generators fight. DC works over
| much longer distances.
| ben_w wrote:
| You would have to build lots of transmission, but the losses
| aren't particularly significant for high voltage lines -- it's
| only about 1000 km from the Shetland islands to Southampton,
| and HVDC transmission losses are quoted at 3.5% per 1,000 km.
| Pricing seems to be a trade secret, but the suggested numbers
| on the Wikipedia page for the 8 GW cross-channel link were
| PS110M for the converter stations and PS1M/km for the undersea
| cable.
|
| I know that a mere back-of-the-envelope calculation isn't worth
| much more than the used envelope it was written on (doubly so
| when it is based on guesstimates of the input numbers), but
| that would be only PS1bn for 8 GW or PS4bn for 32 GW (compared
| to actual average usage of 31.5 GW last year), which is the
| kind of thing that the British government _shouldn 't_ blink at
| but in practice actually faffs and fails at basically all the
| time.
|
| (And the sector is theoretically privatised, so this would have
| to become a business investment, which in turns will have
| potential investors ask inconvenient questions like "What's the
| risk we have cheaper options in 10 years that make this power
| line redundant? And what about those fusion reactors I keep
| reading about in the Sunday Times? What if Scotland becomes
| independent and stops selling you the electricity?")
| ZeroGravitas wrote:
| The supply is in Scotland because the Conservative party
| effectively banned onshore wind in England.
|
| It's not a physical or geographic limitation.
|
| And doesn't apply to offshore wind.
| eigenspace wrote:
| With proper high volatage direct current (HVDC) transmission,
| the transmission losses transporting electricity from Scotland
| to the south of England are not very relevant. It's like a
| couple of percent.
|
| A bigger problem is just the UK's inability to complete
| infrastructure megaprojects on land, so the connectors would
| likely need to go in the sea and take a perhaps inefficient
| route.
| nickdothutton wrote:
| There are a number of problems with wind in the UK. NIMBYism
| means it's either in the north (nowhere near the consumer) or
| out in the sea which is both not terribly near the consumer and
| ferociously expensive to maintain. The UK Energy Catapult
| estimates that a single service vessel "truck roll" or "boat
| launch" (I guess) is something like PS250K. Probably much more
| now as that figure is 10 years old. This means that it makes
| economic sense to wait until you have several broken wind
| turbines before sending out a service vessel. Couple this with
| the fact that they dont seem to have as long a lifetime as was
| promised (various reasons). Finally it is a meteorological
| reality that when it's very cold in the UK and energy demands
| are high... it is also usually very still with no wind, and of
| course in the middle of winter when there are few hours of
| daylight helping us with solar generation.
| cycomanic wrote:
| > Finally it is a meteorological reality that when it's very
| cold in the UK and energy demands are high... it is also
| usually very still with no wind, and of course in the middle
| of winter when there are few hours of daylight helping us
| with solar generation.
|
| Your meteorological reality seems to not correlate with
| actual reality. In the UK the highest energy demand is
| actually correlated with high wind speeds [1]
|
| [1]
| https://iopscience.iop.org/article/10.1088/1748-9326/aa69c6
| s1artibartfast wrote:
| The paper seems to say the opposite:
|
| >This reflects the variation in temperatures and wind
| speeds with season, with calmer, warmer conditions in
| summer and cooler, windier conditions in late autumn and
| early spring. However above the 75th percentile of demand,
| average wind power reduces, which occurs predominantly in
| winter and autumn. Understanding this downturn in wind
| power provides the motivation for this paper. Given our
| interest in high demand days, which predominantly occur in
| winter (figure 1, upper right), only winter days are
| considered.
|
| >The tendency for lower wind power during higher winter
| demand is shown by the tilt of the density contours of the
| daily distribution (figure 1, lower left). It is also
| clearly seen when averaged across days of similar demand
| (figure 2, left). Average wind power reduces by a third
| between lower and higher winter demand, from approximately
| 60% to 40% of rated power.
|
| Look at figure 2. Black is wind power, and the X axis is
| demand. Wind production capacity is down when demand is
| high.
| nickdothutton wrote:
| The very cold days in winter in the UK are always still
| days.
| cycomanic wrote:
| Ok my statement was largely based on the abstract, I only
| skimmed the paper. The abstract refers to the uptick for
| very high demand percentiles (>90%), which I guess is
| still much smaller than the downward trend. I apologise I
| got this wrong.
| s1artibartfast wrote:
| Honest question:
|
| I frequently hear people bring up transmission losses as a
| concern, and genuinely curious where this idea comes from? Was
| this taught in schools or part of some disinformation campaign?
| bigfryo wrote:
| But can we believe anything put out by the establishment when it
| comes to supporting any narrative supported by the establishment?
| Doches wrote:
| One piece of this really jumped out at me: the projection of
| overall energy demand to shrink from 2900 TWh to 900 TWh over the
| next 27 years. The article waives that away by pointing to
| efficiency gains from electrification and decarbonisation -- but
| that's just a stupendous change in consumption over a quite short
| period of time.
|
| I would honestly like a deeper explanation of how electrification
| will produce such a wild decrease! That's shrinking energy use by
| more than 2/3, and presumably after taking into account
| population/industry growth...? Or are the authors just wildly
| pessimistic (not...unmerited) about Britain's trajectory over the
| next quarter-century? What am I missing here?
| steveBK123 wrote:
| It seems sort of nonsensical to project electric usage decline
| as we move from ICE to EV and from oil/gas heat to heat pump.
| Scarblac wrote:
| It's a decline in overall energy, presumably not in
| electricity.
| morsch wrote:
| This is final energy demand and thus presumably includes
| energy used for heating and transportation that's currently
| provided via fossil fuels. In fact, that's the point:
| electrical motors and heat pumps are more efficient, and the
| final energy demand is reduced. In other words, demand for
| electricity goes up, total energy demand goes down.
| steveBK123 wrote:
| That makes more sense if we are talking total energy
| demand.
| gpm wrote:
| The ballpark number for EVs is that they are 4x more
| efficient than ICE cars AIUI.
|
| Harder to ball park heat pumps because it depends on the
| climate, but 4x is probably a reasonable guesstimate. At
| worse it's equal to burning things for heating (when it's too
| cold outside to use heat pumps, not sure that really happens
| in Britain), at best it's... some ridiculous factor better
| (when it's practically the same temperature outside and
| inside).
| raphaelj wrote:
| From what I understand, these TWhs refer to total energy usage,
| not electricity usage.
|
| If you replace a ICE by an BEV powered by solar cells, you
| actually reduce the total TWhs because of efficiecy:
|
| - ICE: 6L of gasoline per 100km, that equals to about 60 KWh
|
| - BEV: 17KWh for the same distance.
|
| The same applies to heat-pumps and some industrial processes.
| conjecTech wrote:
| Correct, a lot of Mackay's estimates fail to account for the
| difference in delivered efficiency between electric solutions
| and their gas counterparts. For instance in his car
| section[1], he estimate you'd need to produce 40kwh to drive
| 50km. That may be close to the true energetic content of the
| gas burned, but you could drive that far on just 10kwh in a
| modern EV, meaning electrification dropped your gross energy
| needs by 75%.
|
| [1] https://www.withouthotair.com/c3/page_29.shtml
| ZeroGravitas wrote:
| He was aware of the benefits of EVs though, from a later
| chapter
|
| > OK, the race is over, and I've announced two winners -
| public transport, and electric vehicles.
|
| He was also very positive about heat pumps.
|
| https://www.withouthotair.com/c20/page_131.shtml
|
| > You've shown that electric cars are more energy-efficient
| than fossil cars. But are they better if our objective is
| to reduce CO2 emissions, and the electricity is still
| generated by fossil power- stations?
|
| > This is quite an easy calculation to do. Assume the
| electric vehicle's energy cost is 20 kWh(e) per 100 km. (I
| think 15 kWh(e) per 100 km is perfectly possible, but let's
| play sceptical in this calculation.) If grid electricity
| has a carbon footprint of 500 g per kWh(e) then the
| effective emissions of this vehicle are 100 g CO2 per km,
| which is as good as the best fossil cars (figure 20.9). So
| I conclude that switching to electric cars is already a
| good idea, even before we green our electricity supply.
| lostlogin wrote:
| And that misses the petrol station thing. Stocking the
| station tanks (and that supply chain), staffing, etc,
| that doesn't cost zero.
| rcxdude wrote:
| True, but neither does maintaining the grid
| smileysteve wrote:
| Marginally and variable costs it does though. A 100%
| capacity charging station has few variable costs compared
| to gasoline delivery; the grid interconnect and charging
| cables are equivalent to filler and tank safety
| inspection, not daily or weekly deliveries of fuel by
| pipeline + truck.
| conjecTech wrote:
| I'm sure he was. It's easy for us to see 15 years later
| that the combination of EVs + solar/wind has a huge
| efficiency gain because you can get to avoid internal
| combustion altogether, but EVs were nascent enough in
| 2008 for that to not be as clear, so those assumptions
| didn't make it into his calculations.
| cpncrunch wrote:
| I think youve misread it. 1600TWh is the demand today. The 2900
| figure is potential supply of wind and solar.
| lucb1e wrote:
| Could you cite where you found those numbers? I can't find
| either of them:
|
| The submission (blog post) doesn't mention the number 900 at
| all; the paper which the submission is about only mentions
| 900 in a footnote saying "Total European [energy] supply was
| 22,900 TWh (IEA, 2022)."; the summary pdf of said paper never
| mentions 900 or 600.
|
| Figures in the paper ending in 600 occur in a few spots, but
| nowhere 1600. There is 21'600 TWh/year (total European energy
| supply, page 8), 16'600 TWh/year (idem), 10'600 TWh/year
| (prior studies' estimates of UK wind resources), and 2'600
| km2 (land occupied by buildings).
|
| But maybe I shouldn't be drawing conclusions based on trying
| to search character sequences in a semi-picture format...
| hwillis wrote:
| > They estimate that it could produce 2,895 TWh of
| electricity each year from solar and wind. That's almost
| double its estimate for final energy demand in 2050. See
| the chart below. [...] We can see this when we look at
| other estimates of energy demand from the literature. The
| National Grid FES projects that Britain will need just 900
| TWh in 2050. [...] Total final energy demand today is 1599
| TWh.
|
| It's right under the first main heading. Just above and
| below the first picture. Searching for 900 in the post took
| me right to it. I have no idea how you missed it.
| marcosdumay wrote:
| Electrification doesn't cause such a decrease. Fixing your
| projection so it's not anymore a "we can't do anything, we must
| keep investing in BP" piece into a realistic one is what
| reduces it.
|
| Honestly, anybody claiming in 2008 that PVs are too expensive
| so we should not invest on them is safe to ignore.
| Gibbon1 wrote:
| That's close to the time frame when I realized solar was
| going to win just based on pure business accounting.
|
| Thing to consider the ultimate price of a manufactured good
| tends to track production volume, device complexity, and
| energy required to produce including raw material.
|
| Solar panels require complex machines to produce but are
| themselves simple, the volume is high at scale, and energy
| requirements are low. That points to something where the
| price is close to the energy and material costs.
| marcosdumay wrote:
| > energy requirements are low
|
| They can surely become low, but currently they are not. The
| EROEI of PV panels is barely on the region where it stops
| being one of the largest factors in its cost.
|
| But yeah, PV has space to improve a by a few orders of
| magnitude more.
| acdha wrote:
| I could believe some reduction if there were massive efficiency
| increases (e.g. replacing resistive heating with heat pumps)
| but that seems impossible on that scale unless they're also
| forecasting entire industries leaving the country.
| ViewTrick1002 wrote:
| Take a look at the amount of rejected energy we waste by using
| for example heat engines today. Electrical engines and heat
| pumps vastly reduce those losses.
|
| https://flowcharts.llnl.gov/
| greenthrow wrote:
| ICE vehicles turn less than 35% of their energy consumption
| into productive work. The rest is waste heat. That's the main
| reason transitioning to pure EVs must happen.
| s1artibartfast wrote:
| IT looks like the 900 number is discussed in chapter 3 of this
| document [1].
|
| As far as I can tell the current usage of 1200 TWh include
| electricity and combustible chimerical energy of gas.
| Electricity use is ~300 Twh, and Gas usage is ~800 Twh.
|
| The proposal is that gas heating would be entirely replaced
| with heat pumps and most gas generation would be replaced with
| modular nuclear reactors and offshore wind.
|
| The numbers are a little misleading because of the way gas and
| electricity are summed to get the top level numbers. A TWh of
| gas consumption is not the same as a TWh of electricity
| consumption. In thier model, 50 TWh of electricity can replace
| 400 TWh of gas. The challenge with this approach is that it is
| not show what is going on with user consumption. Are they
| getting more, less, or the same thermodynamic work done?
|
| https://www.nationalgrid.com/document/138976/download#:~:tex...
| .
| vlovich123 wrote:
| I would bet that electricity demand goes up, not down. When a
| good becomes cheaper/more efficient, demand increases.
| hwillis wrote:
| 1. They're talking about all energy (cars, heat, and
| electricity), not just electricity.
|
| 2. _Demand_ is up in this scenario, not supply, because of
| all the things being electrified.
| bluGill wrote:
| But the change is not a 1:1 linear ratio. Demand increases,
| but only if there is pain that more could use. Once a room is
| bright enough you won't add more light.
| vlovich123 wrote:
| Sure, but you may not be as diligent turning off the
| lights.
| bluGill wrote:
| Exactly, but the improved efficiency is more than the
| loss from leaving it on.
| vlovich123 wrote:
| > Exactly, but the improved efficiency is more than the
| loss from leaving it on.
|
| The improved efficiency needs to be more than the drop in
| marginal cost which is what governs demand, nothing to do
| with how much more electricity you use today. And even
| then, that relationship isn't linear because a 30%
| reduction in cost can drive a 60% increase in demand
| because that reduction puts it in a new price bracket
| where a lot more people can afford it (since wealth is
| non-linear). This stuff is super non trivial and has all
| sorts of higher order effects.
| cycomanic wrote:
| There is no such projection, it seems you misread something.
|
| The O'Callaghan et al. paper (in the Blog post here the related
| figure is fig 1) says that current (2023) demand is 1500TWh and
| current supply is 2885 TWh. There are different projections for
| total demand in 2050 (note all of them project a reduction of
| demand, due to efficiency gains), one of these is the national
| grid FES which projects 900 TWh. Importantly the O'Callaghan
| paper opts to be conservative and choose to use the current
| demand as the demand for 2050. This is conservative, because it
| is higher than all projections which all assume that we get
| demand reduction from efficiency gains.
| cycomanic wrote:
| I want to add that Britain's energy demand has already fallen
| by one quarter in the last 15 years even without the efficiency
| gains from large scale electrification, so a 2/3 reduction
| (which to stress again is not what the paper assumes) is not so
| outrageous.
| nradov wrote:
| Some of that is due to efficiency gains (good). But some is
| also due to deindustrialization and increased imports of
| energy intensive products (bad). We have to look at full
| lifecycle global CO2 emissions in order to perform a valid
| analysis of any changes.
| snapplebobapple wrote:
| The better question is why do they think more efficiency will
| lead to lower use rather than higher consumption? I know, if
| the price stays the same per unit of energy and i stop spendjng
| so much because of efficiency gains, i have a ton of other
| stuff i would love to do that consumes energy so my decrease in
| usage would be tiny. What will decrease my usage is price
| increases, which can only go so far as taxes to capture
| proposed externalities before i revolt and elect someone who
| will axe the tax (as is about to happen in canada).
| bobthepanda wrote:
| Energy use per capita has already been falling for two
| decades in the US: https://www.npr.org/sections/money/2013/04
| /10/176801719/two-...
| snapplebobapple wrote:
| Thats not really what that chart looks like to me, or at
| least the effect is very moderate. The big drops correspond
| to economic shocks. Even if i ignore that the chart is
| topping at roughly 350 in 1975 and bottoming around 310 in
| what i assume is 2023, which makes it what? A 0.22% annual
| decrease?
| kjkjadksj wrote:
| You are making the assumption there won't be some new
| technology that gobbles up significant energy. At one point
| an American's electrical consumption might have been home
| lighting and a radio. Then it jumped by an order of
| magnitude with the refrigerator and air conditioner.
| passwordoops wrote:
| As an aside re: Canadian politics. New Governments don't get
| elected, old ones are voted out of office. The shelf life is
| generally 10-15 years and this government has gotten stale.
| It just so happens the party in position to replace them
| plans to remove the carbon tax (which hasn't been implemented
| in any meaningful way) as part of their platform
| snapplebobapple wrote:
| Thats true but a misinterpretation of the data in my
| opinion. Old ones are voted out because their policies
| mismatch the current pain points, which is definitely
| happening here. Libs were elected on a luxury beliefs
| platform that isn't compatible with the current state of
| the economy/interest rate regime/inflation. Enough people
| have finally realized this to grow disillusioned and change
| voting patterns.that the libs appear to be a bunch of
| kleptos and/or incompetent and/or corrupt is speeding up
| that realization.
|
| If the libs had kept the klepto stuff to a less obvious
| level and adapted the binding parts of their luxury beliefs
| platform they probably would still be polling a majority
| and could have kept this going for quite a while longer.
| immibis wrote:
| The answer to the headline question ultimately doesn't matter.
| Either the answer is "yes", or we figure out how to make the
| answer "yes", or we all die.
| gpm wrote:
| There are other options... nuclear power is more expensive but
| if cost wasn't the issue (e.g. running out of land was) is an
| option.
|
| If cost is the issue there are still risky moonshots like
| "throw tons of money at fusion" (attacking the cost of nuclear)
| and "throw tons of money at high temperature superconductor
| research" (attacking the amount of energy we need), and
| "geoengineering" (risking screwing it up worse). Not guaranteed
| to work, but you know, better than rolling over and dying. Also
| has the side benefit that a lot of the moonshots are worth
| trying anyways.
| immibis wrote:
| Hard reliance on nuclear power is one of the "we all die"
| options. Didn't we learn our lesson about building a whole
| civilization on consuming a limited resource dug out of the
| ground?
| gpm wrote:
| Sure, at least with regards to fission, but it plausibly
| extends the timeline out so that the moonshots are no
| longer quite so difficult.
| kristjank wrote:
| Is it not the case that Uranium and Thorium are not just
| more abundant than existing fuels, but also about a million
| times more energy dense? I find it hard to believe running
| out is a chance we'll face soon.
| ben_w wrote:
| Million times more energy dense, yes.
|
| More abundant? Depends. There's a lot in the sea, which
| isn't currently recoverable. There's a lot we could do
| (but actually don't) with breeder reactors to make more
| fuel.
|
| This means the answer to the question "how long could we
| last on just nuclear fuel alone?" varies from 5.7
| years[0][1] to 4.3 billion years[1].
|
| [0] https://globalwarming-sowhat.com/renewables
|
| [1] https://whatisnuclear.com/nuclear-sustainability.html
| immibis wrote:
| Don't forget about induced demand.
| lucb1e wrote:
| Not like the sun is renewable either. Everything is finite
| if you use enough of it. The problem is that the _old_
| "limited consumable resource dug out of the ground" changes
| our natural habitat as a side effect of creating energy,
| assuming we continue to use it as we do today.
|
| (By that last bit, I mean: powering EVs from coal plants
| with carbon capture at exhausts might be different, idk,
| but probably not cheaper than just not polluting in the
| first place.)
| gpm wrote:
| "Renewable" isn't the best word for wind and solar,
| better would be "use-it-or-lose-it", either you harvest
| it or it dissipates into useless low grade heat. Using
| more of it doesn't deplete the supply of it.
|
| Solar energy (and thus wind assuming otherwise constant
| environmental conditions) is only going to get more
| plentiful for next 5 billion years...
| ianpurton wrote:
| The problem with nuclear is that their is so much FUD around
| it that it becomes not just expensive but very difficult to
| build.
|
| Mainly due to new regulations meaning projects have to re-
| engineer themselves before they are even complete. Leading to
| delays and cost overruns.
| dv_dt wrote:
| The problem with nuclear is that it's slow and expensive to
| build and there is FUD that it is not.
| immibis wrote:
| But it's slow and expensive to build because of
| ReGuLaTioNS. If we just remove all the rEGUlaTiONS it
| could be fast and cheap. What's a Chernobyl?
| WillPostForFood wrote:
| We are all going to die! But nuclear power is to
| expensive, so let's sit in the roads and block traffic
| and subsidize Teslas for rich people.
|
| Either we are under an existential threat, in which case
| nuclear power is an amazingly cheap way to save 8+
| billion people, or there is some other agenda at play.
| gpm wrote:
| The primary constraint limiting the speed at which we
| move away from fossil fuels is cost. Investing in more
| expensive alternatives like nuclear increases the risk of
| the threat becoming existential, and the damage it does
| if it doesn't become existential, compared to investing
| in cheaper alternatives like solar and wind.
|
| It is not a case of "we should do everything" because we
| can't afford to do everything. If we could afford to do
| everything we could easily do a small subset of
| everything and solve the problem.
| WillPostForFood wrote:
| Hard disagree, the primary limitation is availability of
| energy. There is no path to 100% solar + wind + storage
| without mass deindustrialization.
|
| Nuclear would stop being expensive if it was committed
| to. Building 1 bespoke plant avery few decades is not a
| good approach.
| gpm wrote:
| The article is literally about showing that there is in
| fact enough solar and wind energy available to fulfill
| expected (not artificially constrained or
| "deindustrialized") demand.
| WillPostForFood wrote:
| The article doesn't have a plan for storage, and relies
| on a plurality of energy from floating offshore wind,
| which has never been relied on at any scale. There are 4
| windfarms in the world generating just 193MW. You are
| going to bet humanity on that?
|
| https://en.wikipedia.org/wiki/Floating_wind_turbine
| ben_w wrote:
| Superconductors are probably a red herring. It's
| _technically_ possible to make a 1 O global power grid for
| only a few hundred billion in raw materials, a superconductor
| isn 't going to help _much_ with anything except the material
| cost, including but not limited to the cost of actually
| installing that cabling, the geopolitics of where to put it,
| conflicts involving it.
|
| A superconducting cable probably also makes attempts to
| damage the thing easier -- to get 40,000 km of aluminium down
| to 1 O, it needs to have a cross section of 1 m^2, which is
| kinda hard to damage, though also you don't really want a
| single cable because that, with current global electrical
| demand and reasonable (i.e. currently in use) choices for the
| voltage, would be in the order of 1.5 mega-amperes and match
| Earth's geomagnetic field at a distance of about 11 km.
| gpm wrote:
| My understanding is that that if they have nice properties
| they'll enable substantially more efficient
| motors/generators thanks to strong magnetic fields. I can't
| say I'm that confident in that knowledge though.
| revscat wrote:
| Very true, but extremely unpopular to say. The downvotes are as
| expected as they are cause for despair.
| jfengel wrote:
| Even if the answer were "we'll still need 50% from fossil
| fuels" it still cuts CO2 in half. If the answer were "we still
| need 10% for unusual cases", it still means that fossil fuels
| stop being the problem, at least for that one country.
|
| This isn't insurmountable. It doesn't have to be perfect. Even
| a real but incomplete effort makes a genuine difference.
|
| The problem, unfortunately, remains the US, who has a large and
| powerful minority who is convinced it's all a hoax. The
| solution doesn't have to be complete but it does have to be
| something. With many millions of people actively making it
| worse, even 100% in the UK doesn't come anywhere near close.
| dvh wrote:
| There's a lot of assumptions there, wouldn't it be easier to put
| some panels on rooftop, car sized battery in the garage and see
| what happens?
| hn_throwaway_99 wrote:
| The article literally goes into pretty specific detail about
| how much energy rooftop solar could provide.
| morsch wrote:
| I was left wondering why only 8% of roofs quality for rooftop
| solar. I haven't checked the underlying paper, maybe it has
| an answer.
| hn_throwaway_99 wrote:
| That's what I thought was so great about this article. Even
| if you _quadrupled_ the estimate of total rooftop solar, it
| is still just a drop in the bucket compared to the total
| energy generation needed. It 's almost not worth talking
| about because it's such a minor amount of capacity.
|
| I didn't read the paper, but from personal experience:
|
| 1. Rooftop solar depends on lots of individuals to make an
| investment to put solar on their houses. If you say "let
| the government subsidize it", that doesn't really make much
| sense because the government can get a much better return
| on each dollar spent by investing in more efficient
| technologies.
|
| 2. Many roofs are not suitable for solar. They are either
| facing the wrong way, at a bad angle, shaded, or, in my
| case, too "origami-like". Solar panels need to have minimum
| clearance fro ridge lines on a roof, which can drastically
| reduce the total coverable area.
| Tams80 wrote:
| Exactly. It's a quadruple whammy:
|
| 1. Most residences not being suitable for significant
| generation.
|
| 2. The return on investment is decades long (yes, so is
| double glazing, but that is useful for far more
| households), not that most households can afford it at
| all.
|
| 3. The total generation capacity is piddle, especially
| for government investment.
|
| 4. The materials that go into making PV panels are
| horrible to extract.
|
| I'm not saying PV panels are useless, but they are not
| much of anything. Not something my lecturers at uni liked
| hearing/reading, but lo and behold pretty much nothing
| substantial has changed since. They're too busy blowing
| Sustainable Development smoke up their own arses though.
| s1artibartfast wrote:
| rooftop power is basically the most costly and least efficient
| mode of generating power. It many places, it easily costs 10x
| for the same nameplate capacity, and because of suboptimal
| locations and angles, it only produces a fraction of that
| nameplate.
| ZeroGravitas wrote:
| Consumer rooftop is about the same price range as nuclear.
|
| Commercial rooftop (warehouses, big box stores etc) is a bit
| cheaper than nuclear, with the most expensive being the same
| cost as an average nuclear plant, and the low end for new
| commercial rooftop solar being the same as the running costs
| of already built nuclear:
|
| https://www.lazard.com/media/2ozoovyg/lazards-lcoeplus-
| april...
| s1artibartfast wrote:
| You link is broken, is this the same [1]?.
|
| https://www.lazard.com/media/2ozoovyg/lazards-lcoeplus-
| april...
|
| It still shows rooftop clearly to clearly have the worst
| LCOE. I bet the assumptions for Rooftop dont include
| suboptimal builds, like builds in San Francisco, on a north
| facing roof, under a tree, with storage.
|
| Rooftop can be good in niches, but it is hardly a panacea.
| ZeroGravitas wrote:
| It's not clearly worst, since it shows that some rooftop
| solar is cheaper than the cheapest nuclear, there's
| mostly overlap in prices.
| s1artibartfast wrote:
| Im not sure why you are looking at the minimum solar
| costs instead of the average.
| Tams80 wrote:
| We're talking about the UK here.
|
| Ain't no sunshine.
| rcxdude wrote:
| Rooftop power (or other local generation) has a big economic
| incentive behind it, which is that the energy it generated
| essentially goes for residential rates as opposed to
| wholesale rates (which is at least in part actually born out
| by a reduction in the utilization of the grid). So I expect
| it to continue to happen, despite it being less efficient in
| theory than grid-scale. Local battery storage has a similar
| incentive, but even more accessible (at this point, a home
| battery system is likely a better house upgrade investment
| than solar).
| s1artibartfast wrote:
| Selling rooftop energy for residential rates isn't
| economically sustainable, and has already been eliminated
| in California unless you are grandfathered in.
|
| This is because only a small fraction of the residential
| rates goes to production costs, and the rest go to
| distribution infrastructure and operations. Distributions
| and infrastructure costs/ kWh go with more residential
| production, not down.
|
| Think of it this way. With commercial power you might pay
| 0.10/kWh production and and 0.30wh distribution. You can
| make your own rooftop for 0.35/kw, but the grid still costs
| the same or more, so that gets added to your bill.
|
| Residential rates for rooftop solar only ever made sense as
| a huge subsidy for early adopters.
| hn_throwaway_99 wrote:
| I thought this was a really excellent post. The thing I liked
| best about it was how it presented the different set of numbers
| and didn't try to say "one is wrong or one is right", but instead
| tried to explain where the numbers came from, and what the
| outcome would be if some assumptions were wrong so the reader can
| do their own analysis. What I found particularly helpful:
|
| 1. Explaining the difference between MacKay's original
| "technically possible" vs. "practically possible" supply numbers.
| I agree with the article, the world has changed a ton since 2008
| and I do think much more of that technical possibility is now
| practical due to changes in tech and attitude.
|
| 2. One thing I was cautious about is that the lion's share of
| final 2050 supply in the updated numbers comes from floating
| offshore wind, which in my understanding is the _least_
| technologically "ready" solution. Can someone with more
| knowledge comment on this? Is floating wind really as "production
| ready" as would be needed to match these numbers?
| trebligdivad wrote:
| It doesn't seem to mention storage, which for something so wind
| driven is surprising.
| PaulHoule wrote:
| Not one word about storage...
| ZeroGravitas wrote:
| > To be clear: this does not mean that this is the 'optimal'
| electricity mix in 2050. Not least because energy storage costs
| would be very high. We would probably want to diversify a bit,
| not least to help with grid balancing. Before all of the
| nuclear fans get mad: I think there's room for nuclear in there
| too.
|
| > But the point still stands: it seems we have a lot of
| untapped solar and wind resources and they could make up a
| large chunk of our grid, even if they're not 100% of it.
| Tade0 wrote:
| There's one component that could not have been a part of the 2008
| analysis: batteries.
|
| Global annual manufacturing capacity is currently enough to
| produce 50min worth of storage for the whole world (as a fraction
| of annual electricity production).
|
| That's not a lot and it's not utilized fully, but still well
| within the capabilities required to shave off the evening and
| morning peaks - assuming batteries last more than 5 years, which
| is a conservative estimate.
|
| Nuclear would have been a great component here, but IIRC Hinkley
| Point C is still under construction and will remain so until
| 2027.
| Kon5ole wrote:
| A common issue with all predictions from a few years ago is that
| they failed to predict the 90% fall in cost of solar panels. We
| see a similar thing today when battery storage is dismissed as
| being too expensive.
|
| Unfortunately, current policies are often based on predictions
| from a few years ago.
| nradov wrote:
| Battery storage has excellent long term potential but costs are
| falling much more slowly than with solar panels. There are some
| significant constraints on raw materials supplies. Those can
| eventually be worked through but it will take longer.
| Kon5ole wrote:
| You may be right of course, but I believe the reason for the
| slow drop is mostly because most of the battery factories
| currently under production are not online yet and EV makers
| are still grabbing all the batteries they can get. VW just
| started building one of their planned 6 last year.
|
| Once the transition to EV's is mostly done and car sales fall
| to normal levels there will be an immense surplus of battery
| production capacity.
|
| My understanding is also that LFP batteries have basically
| eliminated the raw materials bottleneck, which was another
| development that few analysts (or anyone else) were able to
| predict just a few years ago.
| Gibbon1 wrote:
| Battery economics have really changed in the last 5 years
| without a lot of notice. California has installed 5GW worth in
| the last 4 years. Max demand in California is about 50GW.
| What's driving batteries is the spread between price per MHW at
| 12am and 6PM.
| hn_throwaway_99 wrote:
| When it comes to storage there are also a lot of other
| technologies that may be viable if solar/wind are built out to
| the point where they are particularly over-subscribed (meaning
| that on a particularly windy/sunny day they provide much, much
| more than 100% of demand).
|
| For example, using things like clean hydrogen or Power-to-
| methane processes that can create gas to be used in existing
| peaker plants.
| conjecTech wrote:
| I love this kind of hypothetical analysis, but I'd also like to
| point out there are already people making real strides towards
| this on an individual level in the UK. Youtube channels like
| ElectricVehicleMan catalog what a conscientious person can
| practically accomplish by themselves with readily available
| solutions today. I've particularly been impressed by the
| synergies between rooftop solar, battery storage, and combined
| heat-pump hydronic heat/hot water solutions.
|
| It seems plausible that even a person in a typical row house
| could offset most of their household consumption with solutions
| that will end up with a reasonable return over time.
|
| https://www.youtube.com/@ElectricVehicleMan/videos
| divbzero wrote:
| As OP mentions, David MacKay's _Sustainable Energy: Without the
| Hot Air_ is available for free online:
|
| https://www.withouthotair.com/
|
| The book provides an excellent overview of how different forms of
| energy production and consumption add up and which energy
| solutions could make a real impact. I strongly recommend reading
| it as context for these updated numbers.
| cycomanic wrote:
| I haven't read the book, but my impression from reading this
| Blog post is very poor.
|
| He seems to have written a book dismissing renewables by
| assuming fixed technology/costs from 2008 for projection into
| the future (if everybody did this companies would not invest in
| anything). On top of that he even hand waved the rest away by
| saying their installations would not be accepted by the public.
| That seems to me that he was set out to dismiss solar and wind
| and just looked for numbers to confirm this.
|
| Generally I believe if you want to show the feasibility of a
| technology you should be conservative in your estimates, and if
| you want to dismiss it you should be optimistic in your
| estimates. Ideally you show both conservative and optimistic
| projections.
| RecycledEle wrote:
| I applaud anyone in any side of any issue who makes a good faith
| attempt to do the math and use common sense engineering to answer
| questions.
| theptip wrote:
| Some discussion here about storage, but I am interested in
| modeling around dynamic load shedding / smart grid / "virtual
| batteries".
|
| Seems to me that as the energy mix moves more towards renewable,
| to the extent that the renewable-skeptics' prediction that
| variability is an issue comes true, then we would have to build
| gas peaker plants and start charging more for electricity at peak
| times. In response to this increased market rate delta it would
| become more viable to invest in dynamic pricing and load
| shedding/deferring tech.
|
| So there is a modeling exercise which looks at the peak time
| price premium for various levels of increase in peaker plants
| required as the input variable, and compares that to the
| viability of virtual batteries at those price deltas as the
| output. I haven't seen anything along these lines.
| megaman821 wrote:
| I wonder why oversized hot water tanks don't get more play
| here. You can heat up the water with excess electricity at
| basically any time during the day and it should stay hot for
| about 24 hours if it is well insulated.
| applied_heat wrote:
| In New Zealand they were remotely controlling residential
| customer hot water tanks and heaters with energy stored in
| hot oil using a "ripple" signal on the power lines ...
| probably in the eighties by the age of the equipment I saw.
| hwillis wrote:
| Because people want their hot water to be consistent. Even
| just a simple timer that kicks on the hot water in the
| morning would work, but most people want to have their sink
| still be hot even when they aren't showering.
|
| > it should stay hot for about 24 hours if it is well
| insulated.
|
| It takes 50 kWh to heat a 46 gallon tank up to 140 F. That's
| a ton of energy. Hotter, larger tanks lose even more energy.
|
| Instead, get a tankless heater, backing a small heat pump
| water tank. You get water as hot as you can possibly want,
| heated whenever you want, and it never goes cold.
| megaman821 wrote:
| The whole point of over-sized water tanks isn't to be the
| most efficient, only to supply a lot of demand when at
| times of the day when there is surplus energy. Right now,
| solar and wind are being curtailed more and more.
|
| Also, water consistency isn't that big a problem. Today's
| 120v heat pump water heaters store water at higher
| temperatures and using a mixing valve to deliver the
| desired temperature of water. I am just saying, surely
| electric water tanks, mixing valves, and temperature
| sensors are orders of magnitude cheaper than the amount of
| batteries needed to heat an equivilant amount of water.
| bluGill wrote:
| Tanks can be insulated and larger tanks have less surface
| area per volume so keep heat longer.
|
| My parents 1988 switched their hot water to a plan where it
| was all heated at night. 6 people making no effort to
| conserve water ran out twice in all those years. Yes
| the.water was hotter in the morning. But the last shower of
| the day still needed to be mixed with some cold or it was
| too hot.
|
| Tankless is worse than a large tank. Tankless needs a lot
| more energy now, less over the full day, but when you turn
| the water on it needs a lot now. A tank easily adjusts to
| use power when the power company needs it. Sun shining or
| wind blowing, then heat water to use up whatever is extra.
| Clouds and no wind, just use the stored energy.
|
| Maybe a battery is more efficient, but tanks are cheap
| applied_heat wrote:
| The variability of wind/solar can also be handled without time
| of use pricing by the grid operator including terms in the
| energy purchase or interconnection agreement requiring the
| generating facility to maintain some degree of consistency to
| the output. Then it is up to the generator to figure out how to
| do that, perhaps with batteries.
|
| The problem we saw in Ontario when the market was introduced in
| 2001 or so was that it was politically unfavorable to have the
| extremely high prices, even for an hour let alone long term,
| that would encourage an investor to build a storage facility.
| theptip wrote:
| I think ideally you set up the market so that supply or
| demand can move to meet these fluctuations. Agree it's
| politically sensitive, but if you artificially flatten the
| price curve then you remove consumer incentives to
| participate in solving the problem.
|
| I suspect industrial/commercial power usage is the big area
| for innovation here, but would love to see a breakdown of
| where the low hanging fruit is.
| hwillis wrote:
| > Seems to me that as the energy mix moves more towards
| renewable, to the extent that the renewable-skeptics'
| prediction that variability is an issue comes true, then we
| would have to build gas peaker plants and start charging more
| for electricity at peak times.
|
| There are a lot of different types of variability. You're
| talking about sudden short-term variance in supply, which is
| easy to deal with- just build more renewables. Bad weather
| doesn't cover up entire states except for extreme events, and
| you can just turn it off when it isn't needed. You can build a
| _lot_ of overcapacity if the alternative is to pay peaker plant
| rates.
|
| Increased variance like I interpret most people talking about
| it is those extreme weather events not necessarily hurricanes,
| but things like a week of no wind or heavy clouds happening to
| cover every panel in a distribution area. The fear being that
| you would still need gas plants or huge batteries to run for
| that one week a year, at extreme cost. The variance averages
| out _most_ of the time, but not _all_ the time.
|
| Virtual batteries work with the former, but not the latter.
|
| > In response to this increased market rate delta it would
| become more viable to invest in dynamic pricing and load
| shedding/deferring tech.
|
| It's definitely not a tech problem. It's an incentives problem.
| The tech was always incredibly simple, and it does literally
| exist already- you can buy internet-connected thermostats. All
| you need to do is connect Nest to your local electricity
| distribution company and tell it how many degrees colder/warmer
| you will tolerate per $ saved. 45% of a house's energy use is
| in controlling the temperature of air and water (and that's not
| counting the fridge, which is another 7%).
|
| It's as much on the suppliers as it is on consumers, IMO.
| Electrical distributors are some of the laziest, worst-run
| companies in the country. Half of them can't even do _billing_
| right; I know dozens of people who have been double charged or
| never charged or charged for their neighbor- nobody wants to
| read their electrical bill, so nobody cares. The average US
| household spends ~$2450 on electricity annually, and the amount
| you can save for how complicated it is is just below that
| mental threshold.
|
| I don't see it getting better without legislation. Most
| obviously, a push for subsidized smart meters that don't use
| 1930s tech to measure electricity. Then a standardized
| (extensible) API and/or reporting requirement, so that devices
| can know the current price of electricity. A standard for
| transmitting that info over the house circuits themselves, if
| you're feeling fancy. Direct-to-consumer subsidies from grid
| authorities for things like ancillary services, power factor
| correction, and frequency stabilization.
| theptip wrote:
| > You're talking about sudden short-term variance in supply,
| which is easy to deal with- just build more renewables.
|
| Easy as in simple, but I think this dramatically skews the
| price viability. If I need 2x overcapacity then the price to
| the consumer is 2x per MW of base capacity, and it's no
| longer viable to use solar over gas.
|
| > It's definitely not a tech problem
|
| I disagree. I'm aware of some existing options, my claim is
| that with a bigger delta, more options become viable to
| research and implement. For example there was a thread
| recently where we discussed modulating energy usage in
| aluminum smelting, which requires a new design for the
| furnace to keep the temperatures stable. (This tech already
| exists, but AFAICT it's not cost-effective to deploy widely.)
|
| There are lots of industrial processes which could
| conceivably modulate their power consumption, but it's not
| currently cost-effective to even design these improvements at
| current levels of peak premium.
|
| Tech is downstream of incentives, is what I am saying, and
| price signals can be a good incentive; many claim that 100%
| renewable is not viable because of the cost of closing that
| last 1% of daily variability, I am hypothesizing that the
| system as a whole could, with appropriate price signals,
| build the tech to make the demand curve much more mutable.
|
| This gets at seasonal variability; if we have a week with
| lower energy production, then the peak-premium goes up, and
| maybe we turn off the marginal industrial, residential, and
| commercial consumers.
| bluGill wrote:
| You need most of that over capacity anyway. They still keep
| generators from the 1920s operational just in case a storm
| cuts off one town from the grid, turn on those generators
| and let the linemen fix it a week later
| theptip wrote:
| I'd like to see numbers backing up this assertion,
| because everything I have seen suggests the opposite at
| grid scale. Sure, remote towns will have backups, but the
| major metro areas do not run at substantial overcapacity
| ratios. (Else, peakers would not be a thing.)
| nradov wrote:
| Heavy clouds often do cover multiple states (or European
| countries) simultaneously. But the bigger problem for places
| like the UK and the USA is that the major grid interconnects
| run East so when peak daily demand hits it's already getting
| dark in the places from which they can easily import
| electricity.
| nradov wrote:
| Dynamic pricing and load shedding can reduce the need for
| peaker plants and storage systems. But as a side effect it will
| also drive energy intensive heavy industries offshore. Certain
| types of industrial facilities can't just start and stop, and
| every minute they're offline they're losing money. Major
| countries have to keep certain strategic domestic industries
| operating regardless of the cost or environmental impacts; it's
| just too risky to depend on imports that could be interrupted
| at any time due to a war or other geopolitical crisis.
| ilaksh wrote:
| The missing piece is renewable fuels. Having some kind of
| hydrogen or ammonia, biodiesel etc. from solar and wind and
| available to supplement real-time generation when needed would
| make it much more feasible to drop fossil fuels.
| jacquesm wrote:
| Those would require a massive surplus of Solar, Wind and Hydro
| which we currently do not have. It may come to that but right
| now the surplus happens at best during a few minutes to 10's of
| minutes at peak solar in the summer, the rest of the day (and
| the rest of the year) we are running at a substantial deficit
| that is still made up from fossil fuels or nuclear.
| Tams80 wrote:
| The issue there is that there are a few very vocal renewable
| energy proponents who just don't get that at all.
|
| Merely mention 'hydrogen' and they go into a tirade.
|
| Though really, the biggest issue is apathy.
| rcxdude wrote:
| The efficiency is pretty awful, though. It's quite hard to make
| the economics of it work (even if the electricity is free) with
| current fuel prices, which is why it's not really happening.
| Either the tech needs to get a lot better or the fuel needs to
| get a lot more expensive (which I don't imagine would be a
| popular option).
| DonHopkins wrote:
| Locking up SBF was a step in the right direction. Now do the rest
| of the energy wasting Bitcoin shills!
| jl6 wrote:
| One thing I didn't appreciate until recently is how big Britain's
| EEZ is. If floating wind turbines can be made practical, there is
| huge opportunity not just for energy self-sufficiency, but for
| export too.
|
| P.S. even if the numbers have been superseded, MacKay's original
| book is still worth reading because it's so fantastically clear
| in how it lays out the basis for estimation.
| simonbarker87 wrote:
| If you haven't read the book "Sustainability without the hot air"
| by David MacKay then I strongly recommend it. He makes some
| assumptions that may not stand the test of time but overall it's
| well reasoned and he explains the maths and logic well.
|
| His passing is a real loss to UK science.
|
| I got to see him speak once, very engaging and his passion was
| clear.
| anovikov wrote:
| One thing i don't like about this analysis is when final energy
| is expressed in TWh, which is a unit normally reserved for
| electricity. That creates confusion.
| hn_throwaway_99 wrote:
| Watt-Hours is an extremely common metric to use for total
| energy when talking about societal-wide energy consumption.
| hinkley wrote:
| I just finished, "How Big Things Get Done", I think on a
| recommendation some time back from someone on HN.
|
| He says that among the projects that tend to be on time and on
| budget, roads, solar and wind are three of them. While he doesn't
| say it, I read this as "all large successful projects start as
| small successful projects". Once you've built 10 miles of road
| the next 10miles is mostly more of the same, subsurface
| conditions notwithstanding. Once you've installed three wind
| turbines in a field installing the rest looks much the same
| (getting the first one in required solving a bunch of
| transportation problems of course). The teams just get a little
| faster with each one, because they are iterating on a pattern
| they already know.
|
| You try to build a nuclear power plant and it might not show up
| until after the politicians who pushed for it to be built have
| retired. Which means it might not show up at all because all of
| the skin has left the game. But if I try to cap my career as
| governor with a new wind or solar farm? I may actually get to cut
| the ribbon.
|
| It makes me feel a bit better about our prospects that solar and
| wind are easier logistical problems than repeating the old
| patterns.
| credit_guy wrote:
| > You try to build a nuclear power plant and it might not show
| up until after the politicians who pushed for it to be built
| have retired.
|
| You can try to reactivate nuclear power plants that were shut
| down.
|
| I state I live in (New York) closed 2 nuclear reactors in 2020
| and 2021, each providing more than 1 GW of clean electricity.
| Both reactor were closed because of political pressure. If we
| were to apply the reverse political pressure, I think we could
| have them up and running in 5 years, if not sooner.
| jonplackett wrote:
| What is the running cost of doing something like this? How often
| do they need to be replaced and can we afford to do that for the
| long term?
|
| Also - what about the geopolitics. The reason solar is cheap is
| because china. Do we want all our energy needs to be dependent on
| China? Although we are still building Hinkley Point C with
| Chinese investment anyway so -\\_(tsu)_/-
___________________________________________________________________
(page generated 2023-11-05 23:00 UTC)