"The future is here, just unevenly distributed... " and the cool thing for the rest of us is that the learning curves on solar, especially, and battery power are incredible, so some people adopting now hastens the day when it is here for the rest of us.
More and more use-cases will pop-up as the cost of solar tech slowly inches down.
When you consider it, most of our roofs are unused, and would make an ideal location for tiny panels + battery packs. Similarly new blocks of city development can be planned around a central panel+pack with housing surrounding it.
In a foggy/dreary climate (think UK) it doesn't make sense
Same with places prone to radical weather. Or just anywhere that doesn't get a lot of sun (the farther you get from the equator, really).
Because even if we get solar panel cost down in the next few years, it is still going to be expensive and need a fair amount of maintenance. And if that doesn't offset the cost sufficiently, it isn't worth it
Believe me, I want clean energy and do think solar should be exploited where it is reasonable (same with wind) and wish we would at least use cleaner sources where it isn't. But studies/experiments like this tend to rely on best case scenarios and corner cases and often just don't take economics into consideration.
Are they good as proof of concepts and PR? Yeah. But they still aren't that representative.
PV doesn't have to be the best tech everywhere. Nuclear and coal has it's own drawbacks - hard to turn on/off and generating a lot of unneeded power during night.
Which I think is where solar/wind/hydro (in places that aren't the hoover dam...) make the most sense. Topping off comparatively clean sources like nuclear (or, preferably, actually clean sources) either through only turning them on when needed or having them charge capacitors. Hell, the UK have even been doing it, to a lesser extent, through pumped storage (think of them like really big water-based capacitors that you charge during non-peak times)
My point was more in balancing out the common misconception of "Let's just put a solar cell on every roof".
Interestingly, Eigg, a small hebridean island off the west coast of Scotland has been operating 95% of their power on renewables since 2008: https://islandsgoinggreen.org/about/eigg-electric/ (they keep diesel to drive baseload backup)
The initial reason for this was that to get electricity from the grid to them was going to cost _lots_ of money. Solar is an important part of their mix - the Hebrides get a a good chunk of sun in the summer (and long days too). They've been a case study for a number of similarly isolated communities - either islands or other locations far away from existing electricity infrastructure.
Making batteries more efficient (and cheaper), and making each of the renewables mix more efficient and cheaper will make this possible for more and more communities.
> Interestingly, Eigg, a small hebridean island off the west coast of Scotland has been operating 95% of their power on renewables
Renewable, but mostly as hydro.
Things are easier when you have large hydro (relative to your needs), Iceland's electrical production has been 100% renewable since 2008 (and was 99.9% renewable before that) because they have a ton of hydro (80% of total capacity), and a fair amount (and growing) of geothermal (geothermal is 2/3rd of their energy consumption but the vast majority is direct use for heating, not electricity generation). And note that ~70% of Icelandic electricity generation is solely for aluminum production.
Hydro is the main provider for sure, and like in the case of Iceland made the whole thing possible when solar was more expensive and less efficient. Numbers from the link in my comment above:
> Three hydroelectric generators produce electricity from running water. The biggest hydro above at Laig on the west side of the island is 100kW, with two smaller 5-6kW hydros on the east side.
> Four small 6kW wind turbines below An Sgurr
> 50kW Photovoltaic array producing electricity from the sun.
> Although the capacity of the scheme is around 184kW, not all renewable resources produce their maximum output all the time or at the same time.
I think this means that solar would provide 27% of their total coverage if everything was running at full capacity (which never happens). Long summer days with low cloud coverage at time of low wind makes solar an important part of their summer mix.
They're also experimenting with using solar on homes to heat water to see how much much less fuel they burn.
>The sun can be used to heat water instead of fuel. Solar panels are being installed by islanders on three homes on Eigg to test how much less fuel is being burnt, and how much money is saved.
I believe links connection the UK to Iceland and Norway are at the planning stage and generally interconnecting over lager areas is part of using renewable energy more efficiently.
It has wind power, sea water sourced heat pumps, a little bit of solar, a test rig for underwater wave power, batteries that are used to relieve the peaks on energy transmission to the mainland and projects to increase electric car uptake to soak up excess energy production.
>In a foggy/dreary climate (think UK) it doesn't make sense
No, but wind energy does make sense and the UK already generates rather a lot.
>Believe me, I want clean energy
People say this but it seems rather easy for astroturfers to kill green energy projects in the UK based upon the flimsiest of pretexts (e.g Navitus Bay Wind Farm Proposal).
Do you want to know why so many of these initiatives fall apart? Because they get sold as pipe dreams. We'll just throw solar cells on every roof (what I was actually replying to) and free energy for all! Yeah! We'll power the entire planet! Disagree with me? Screw you, you are just working for big oil!
No. We need to be realistic. In some regions, solar is the bomb diggety. In others, wind can generate a lot of watts. And pretty much anywhere that has hydro or geothermal as an option do great. And in a subset of those, it is sufficient to handle power needs.
So sell it that way. Don't perpetuate the myth that we are "just about there" because that makes it an easy target. Explain that it is still mostly about supplementing power and lessening dependencies. Because pushing the former just leads to "Your proposal will handle about a quarter of non-peak energy usage. And it will take at least a decade until it might get to 50?"
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Also, you may want to consider reading other branches as most of your points (aside from the accusations of astroturfing...) were already brought up in other branches. And you'll see that I even praise the UK.
I think when many people say "I want clean energy" they're not actually all that bothered.
That's how proposals like the one I mentioned get killed off. Oil/gas interests can gin up a tepid nimby backlash and with a nod and a wink get the government to kill them off in response, and the government pays no political price for it.
Meanwhile, a Chinese run nuclear project that makes NO financial sense gets government subsidies and fracking gets the go ahead largely because of who the Tories are friends with.
This is the reality of green energy these days: it's not market forces keeping it down, it's being kept down by active suppression of market forces.
>Do you want to know why so many of these initiatives fall apart? Because they get sold as pipe dreams.
Are you saying that the Navitus Bay proposal was a pipe dream?
>So sell it that way. Don't perpetuate the myth that we are "just about there"
Jesus Christ. I tried to be polite but I'll just outright say it: Don't be a dick. You are falling into the trap of "You aren't pure enough for me so you are evil" that is so common.
And you are once again picking a single metric to compare against (seriously, read the other branch where there is a great discussion that breaks things down a lot better with respect to an island off the coast of Scotland).
Price per kilowatt-hr is one metric that is worth considering. So is kw-hr per square mile, installation costs, maintenance costs, and many others. Not to mention that a lot of those metrics assume optimal conditions which might only exist for a portion of a given day (or year...). The reason why filthy sources (oil and coal) and comparatively clean (nuclear) energy are used is that they are consistent. It doesn't matter if it is a bright summer day, a cold and windy night, or just a dreary morning: They make the same amount of energy per unit resource (mostly. There are actually a lot of caveats).
But, as mentioned, they are a lot harder to fine tune. And they result in a dependence on expensive resources and are bad for the environment (nuclear isn't AS bad, but it is still pretty crap). That is where clean sources like wind and solar come into play for the vast majority of the planet. We can drastically lower our dependence on dirty sources by using clean sources to supplement and wean us off of dirty energy.
But I guess I am not ideologically pure enough for you (or, at least, the small snippets of my posts aren't).
Most people live where solar makes sense, and that's only going to be more true as a) more people are born in those locations, b) more people move to those locations, c) those locations expand as solar gets cheaper, and storage becomes cheaper.
The UK is surprisingly far north. It's always surprising to me what North American places line up with European ones. Luckily for northern Europe, they have lots of other renewable resources to make up for the lack of sunshine.
I think possibly your opinion on Solar is a bit too UK-centric, since it's already very competitive in other locations, particularly anywhere that air-con is commonly used since that electric load is correlated with solar activity.
For single family residences, yes this is true. The roofs of commercial buildings are often littered with HVAC equipment, antennas, patios, lots of other things. Plus the more stories you have in a building the smaller the ratio of roof area to building area, so you have less space to generate power for more people.
There's definitely a lot of room for growth for solar, but it's not a panacea. I'm looking forward to what we can come up with.
I found some price data on another island project, a Tesla battery installation on Kaui[1], $0.145/kwh for stored power. The end user price in Hawaii is around $0.33/kwh. While that's not a cheap price for storage, LiIon batteries are on a rapid price decline because of manufacturing learning curve. Net net, it looks like they're just breaking into the cost-effective zone and within a few years will be practical in many places.
> The Tesla Energy batteries will supply a 52 MWh utility-scale energy storage system in order to help KIUC meet evening peak demand, which typically occurs between 5:00 pm and 10:00 pm... SolarCity said it would charge the utility 14.5 cents per kilowatt-hour for power from the batteries in a 20-year arrangement
I hope they can pour money into technology which generates power from the rain[1].
As with everything the new technology starts out with low power. But my hope is that they increase that and you can generate energy all year round. Even at night!
> Ta'u previously had to run on diesel generators. That burns 300 gallons of fuel per day, which is neither eco-friendly nor cheap. Solar eliminates the pollution [...]
I wonder about the ecological footprint of the batteries though.
Once built, you can use and reuse the materials that went to the battery almost indefinitely. The stuff inside the battery does not get consumed, it just changes form. And once you have used all the cycles, you can take the battery apart, leaving you with the stuff you began with, ready to be assembled into a new battery. So if you generate all your energy via solar, you only need sunlight to charge and recycle them all.
Current Li-on packs are good for 2000 cycles, about 8 years. Even when you include mining and manufacturing the environmental impact is still negligible compared to running on diesel 24/7/365.
I believe Tesla is giving these pack a much longer life span. I know one of the chief engineers for their batteries said the old batteries that exist in the Model S and X today could last many more cycles with a 15-20 year life span. I think we're seeing good evidence of this too as Tesla's are reaching 100k+ miles, one got to 200k already and I believe only had ~11% battery degradation. Pretty impressive either way.
As far as mining, I think the biggest issues as far as cost go are getting Cobalt, which is primarily only found in the DR Congos', and then in Tesla's case, finding more Lithium in North America.
I'm sure in a ~5 years or so, Tesla will create a massive battery recycling program as well to start bringing in those Tesla batteries on cars from the early models.
> I believe Tesla is giving these pack a much longer life span.
Tesla's CTO is giving the battery packs a 10-15 year minimum service life.
> I'm sure in a ~5 years or so, Tesla will create a massive battery recycling program as well to start bringing in those Tesla batteries on cars from the early models.
Tesla plans a recycling line at the Gigafactory. Old batteries in, new packs out.
Note that your 8 year number has 2 assumptions buried in it: (1) that batteries are discharged/charged every day, and (2) that batteries need to be replaced once they reach ~ 70% of their original capacity.
Neither of these assumptions is apply to grid-scale storage. For (2), you can install 30% new capacity and keep the old batteries in service. And for (1), the size of the battery storage is dictated by wanting to last 3 cloudy days... which rarely happens. So you might only cycle 1/3 of the batteries on an average day.
All I have is the industry numbers. On average they all claim 1000 cycles at 80% DoD. They'll certainly get longer usage given a lower DoD, but if they design a bare bones system it could have enough to last 1,3,5, or 10 days
In reality, with somewhat deep discharges, the number is actually closer to 600-700, before experiencing significant capacity losses of ~15-20%.
At 2000 cycles, I'd imagine the capacity to be somewhere in the range of 50% of initial. Now that doesn't matter for utility scale, because you can easily keep that 50% pack in operation, as long as your total capacity stays the same (adding new packs), but for smaller scale, it's quite significant.
Look up Nissan Leaf range degradation and you'll see what I mean.
I'm actually a Leaf shopper so I have looked into it. From what I understand the degradation comes from the older design being aircooled. In southern climes this won't work for long. The Leafs from 2015 are using a liquid-cooled pack. Older models are getting them replaced under warranty.
If you need 10kg Lithium for one Powerpack (100g Li for 1kWh), you need about 500 times more Li on planet earth to have enough Powerpacks for everyone? Nice solution for mankind. But we will go to Mars anyways.
We are currently mining about 600,000 tones of lithium per year. That's enough for 60 million powerpacks per year. I really don't think that it's one powerpack per person, these are utility scale installations. If it's 1 powerpack per 10 people, it'd only take 10 years are current lithium extraction rates to build enough for 6 billion people.
There is an estimated 2.55 × 10^10 kg potentially economically extractable lithium available on the Earth. At current extraction rates that's "gone" in 42 years. Fortunately, lithium is recyclable.
But Earth itself, no, your figures are way off. There is 2.3 * 10^14 kg in seawater alone.
Thanks, interesting article. Just read it briefly yet, but it looks like it's author summs up with that there is not even enough Li for building batteries for some billion cars.
There are 14,000,000 tonnes of identified reserves. There may be more, we just haven't identified them yet.
Estimates for the Earth's crustal content range between 20 ppm and 70 ppm. Using 20 ppm and the mass of the Earth's crust being more than 2 * 10^19 tonnes, it would be (20/10^6) * (2*10^19) = 400,000,000,000,000 tonnes of Li.
So although we'll only ever be able to mine a small fraction of that, I still think it's safe to assume that we are not capped at 14 million tonnes.
I don't think its recyclable in any efficient way - smelting wont do it, it has to be complex chemistry. More complex than mining was originally. So we're not going to do that until mining quits working.
From all I have read, lithium supply does not seem to be a major concern [1]. But if your numbers are correct, note that the currently mined lithium reservers are 14,000,000 tonnes [2]. 1 tonne lithium then gives you 10MWh of capacity. So 140PWh sounds like a lot of capacity, and this assumes we just stick to places that are currently minded and don't explore alternatives like extraction from seawater [3].
Your statement only makes sense if you have the strange assumption that something that is a good solution for an isolated island is also a good solution for everybody else.
On large continental grids you can do a lot of things to reduce the need for battery storage, e.g. transporting power over distances, demand side management in large factories and using other terrain-dependent storage technologies like pumped water storage.
Certainly at some point fixed installations will move to sodium. But this is not now, and when we get to that point, we'll be able to get the lithium back to reuse on something else.
I think this is because Tesla/SolarCity/SpaceX has this philosophy of versatility of components. They want to have one and only one energy storage technology and produce it at scale. This also one reason for the Tesla/SolarCity merger: you can use the same building block and scale it up.
SpaceX is doing the same: use one rocket motor on booster and upper stage, and mass produce it. In contrast Ariane uses three different motors on one rocket.
This is one of those really important business decisions that feels almost trivial but with profound positive results. It immediately reminded me of Southwest Air and how they credit some of their early success to _only_ flying 737s. Letting them standardize their maintenance and getting very good at keeping that one model of airplane flying.
This is currently happening with Canadian airline WestJet. For many years they only flew a single aircraft which made maintenance much easier (staff trained on a single aircraft, parts are easier to keep in stock). They since purchased a few larger aircraft to fly to London and Dublin and have been plagued with maintenance issues. Passengers are getting stuck in London while WestJet scrambles to fly in a mechanic and parts to fix the planes.
The computer industry is perhaps the most extreme example of this. From a dizzying array of different systems in the infancy of computing, the overwhelming majority of the market has consolidated to two instruction set architectures and a handful of operating systems. Magic things happen when your economies of scale are big enough.
While your argument makes sense for Tesla/SolarCity specific case, there's no reason that the same efficiencies of scale could not be applied to flywheels overall for energy storage.
The additional benefits of batteries over flywheels however is that utility-scale energy storage can be achieved with a wide range of battery quality. What I mean by that is that say, for example, a batch of batteries doesn't pass QC to make it into the Tesla cars by virtue of having only 85% of their desired capacity. They can still be used in energy storage facilities.
Same goes for used battery packs from Teslas that have degraded to 70-80% of their original capacity over the years. I surmise it's quite more efficient to use these packs for grid storage than to recycle them right away. Space is probably not a huge constraint for them, so it's not a big deal to use packs that operate in the lower capacity ranges.
Think of it as a big energy storage cloud like Backblaze's storage pods. They mix and match consumer grade hardware, but because of scale and redundancy, they can get away with it and still provide reliable storage.
Same goes for energy.
I'm not quite sure what the scales are for flywheel manufacturers compared to Tesla's gigafactory, but they're probably at least an order of magnitude smaller, plus flywheels generally can't be used as the main source of power in cars or portable electronics, while Li Ion cells can.
I'm sure there are tradeoffs for both. Seems like flywheels would need some significant maintenance when compared to battery banks. The advantage here is that different Islands are trying different technologies. This will allow a long term analysis of those tradeoffs and costs.
Flywheels have very different properties from battery storage. Most notably flywheels loose a lot of power over time and are mostly good for short term storage. So it depends a lot on the situation which technology makes more sense.
In the case of that Island I assume what they need is that over longer timeframes they have enough sun and can store the oversupply of electricity for a relatively long time, because the occassions when there isn't enough sun are rare.
Flywheels with air-bound rotors on mechanical bearings do, flywheels with vacuum-bound rotors on magnetic bearings don't as most of the losses are frictional.
Tesla seem to be making a bet on manufacturing scale reducing the price of batteries from where it is now. This applies to cars and storage, and obviously using it for both further amplifies the price reduction.
IIRC, safety measures for high-energy flywheels end up being pretty expensive. Basically, if the wheel or bearing fails, something is going to get seriously fucked up, and an appropriate sacrificial structure is a task in itself. I was once told of a physics lab that, rather than attempting a containment structure, was located next to miles of forest in case its flywheels, er, escaped.
Keeping them underground seems like the simplest solution when starting from scratch. Adding flywheels to an existing structure is a much tougher problem.
In datacenters, the purpose of a flywheel is to bridge from the start of a power outage to generator power being available. In that scenario, you don't need batteries.
If you have batteries, they can come online as fast as a flywheel.
A bit of searching suggests that flywheels cost at least 4x as much per kWh. Even if batteries don't improve over time, it's cheaper to set up a battery system and replace it three times as often.
Battery tech in general is really the limiting factor for environmental improvements of solar and wind over other common forms of energy. We need more advances here, and they shouldn't all come from Elon Musk.
One of the toughest things to overcome is that lithium ion batteries have a limited lifespan (although it's improving) and the cost for that life span compared to alternatives is pretty high, so the economics aren't great. Yet.
The environmental hazards, both in manufacturing and disposal, are not insignificant either[1].
With all that said, li-ion represents our best bet for future tech advances that have minimal environmental impact, especially for space travel.
Eventually. (But if I was a VC, I'd be investing in cleaner and more efficient ways to utilize petrochemicals in the near/mid term.. maybe looking at non-burning tech; whatever happened to fuel cells?)
It's already out. Toyota will only sell you one if you live near a hydrogen filling station, which are few and far between at the moment.
Hydrogen is looking like a dead duck, at least as an automotive fuel. The Mirai costs about the same as a mid-range Tesla Model S. I know which I'd rather own.
Fuel cells are low efficiency (<60%) and expensive so they are a poor fit for grid energy storage. One option is to just burn hydrogen in traditional gas turbines which can also have 60% efficiency ed: (62.22%), but are much cheaper to build.
PS: This also simplifies the problem to: Can you make and store hydrogen for a lower cost than natural gas.
Someone under shadow ban mentioned the inefficiency of electrolysis. Which is also around 60% at best.
That is an important consideration, but on a national level it may still be useful as redundant capacity. If your hydrogen tanks are fill up over months when production is vastly above demand, and only used in very rare situations then it might still be viable. At that point it's more a question of economics then thermodynamics.
However, the standby generators which use this hydrogen are a more direct comparison in cost and efficiency terms.
The 'limited lifespan' of lithium batteries ma not be such a deal killer in the near term. As batteries in cars get used up, they aren't dead, they are just not powerful enough to be carried around anymore. After that, than can be put to use in stationary power while they continue to degrade.
I suspect this is one of the reasons the powerwall makes so much sense for Tesla. The battery comes out of a car and then they re-sell it to go into somebodies house.
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[ 3.1 ms ] story [ 168 ms ] threadWhen you consider it, most of our roofs are unused, and would make an ideal location for tiny panels + battery packs. Similarly new blocks of city development can be planned around a central panel+pack with housing surrounding it.
https://books.google.co.uk/books?id=q1FyDAAAQBAJ&pg=PT1613&l...
Same with places prone to radical weather. Or just anywhere that doesn't get a lot of sun (the farther you get from the equator, really).
Because even if we get solar panel cost down in the next few years, it is still going to be expensive and need a fair amount of maintenance. And if that doesn't offset the cost sufficiently, it isn't worth it
Believe me, I want clean energy and do think solar should be exploited where it is reasonable (same with wind) and wish we would at least use cleaner sources where it isn't. But studies/experiments like this tend to rely on best case scenarios and corner cases and often just don't take economics into consideration.
Are they good as proof of concepts and PR? Yeah. But they still aren't that representative.
My point was more in balancing out the common misconception of "Let's just put a solar cell on every roof".
The initial reason for this was that to get electricity from the grid to them was going to cost _lots_ of money. Solar is an important part of their mix - the Hebrides get a a good chunk of sun in the summer (and long days too). They've been a case study for a number of similarly isolated communities - either islands or other locations far away from existing electricity infrastructure.
Making batteries more efficient (and cheaper), and making each of the renewables mix more efficient and cheaper will make this possible for more and more communities.
Renewable, but mostly as hydro.
Things are easier when you have large hydro (relative to your needs), Iceland's electrical production has been 100% renewable since 2008 (and was 99.9% renewable before that) because they have a ton of hydro (80% of total capacity), and a fair amount (and growing) of geothermal (geothermal is 2/3rd of their energy consumption but the vast majority is direct use for heating, not electricity generation). And note that ~70% of Icelandic electricity generation is solely for aluminum production.
> Three hydroelectric generators produce electricity from running water. The biggest hydro above at Laig on the west side of the island is 100kW, with two smaller 5-6kW hydros on the east side.
> Four small 6kW wind turbines below An Sgurr
> 50kW Photovoltaic array producing electricity from the sun.
> Although the capacity of the scheme is around 184kW, not all renewable resources produce their maximum output all the time or at the same time.
I think this means that solar would provide 27% of their total coverage if everything was running at full capacity (which never happens). Long summer days with low cloud coverage at time of low wind makes solar an important part of their summer mix.
They're also experimenting with using solar on homes to heat water to see how much much less fuel they burn.
>The sun can be used to heat water instead of fuel. Solar panels are being installed by islanders on three homes on Eigg to test how much less fuel is being burnt, and how much money is saved.
https://www.youtube.com/watch?v=FXe1hBvlylw
It has wind power, sea water sourced heat pumps, a little bit of solar, a test rig for underwater wave power, batteries that are used to relieve the peaks on energy transmission to the mainland and projects to increase electric car uptake to soak up excess energy production.
No, but wind energy does make sense and the UK already generates rather a lot.
>Believe me, I want clean energy
People say this but it seems rather easy for astroturfers to kill green energy projects in the UK based upon the flimsiest of pretexts (e.g Navitus Bay Wind Farm Proposal).
Do you want to know why so many of these initiatives fall apart? Because they get sold as pipe dreams. We'll just throw solar cells on every roof (what I was actually replying to) and free energy for all! Yeah! We'll power the entire planet! Disagree with me? Screw you, you are just working for big oil!
No. We need to be realistic. In some regions, solar is the bomb diggety. In others, wind can generate a lot of watts. And pretty much anywhere that has hydro or geothermal as an option do great. And in a subset of those, it is sufficient to handle power needs.
So sell it that way. Don't perpetuate the myth that we are "just about there" because that makes it an easy target. Explain that it is still mostly about supplementing power and lessening dependencies. Because pushing the former just leads to "Your proposal will handle about a quarter of non-peak energy usage. And it will take at least a decade until it might get to 50?"
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Also, you may want to consider reading other branches as most of your points (aside from the accusations of astroturfing...) were already brought up in other branches. And you'll see that I even praise the UK.
No.
I think when many people say "I want clean energy" they're not actually all that bothered.
That's how proposals like the one I mentioned get killed off. Oil/gas interests can gin up a tepid nimby backlash and with a nod and a wink get the government to kill them off in response, and the government pays no political price for it.
Meanwhile, a Chinese run nuclear project that makes NO financial sense gets government subsidies and fracking gets the go ahead largely because of who the Tories are friends with.
This is the reality of green energy these days: it's not market forces keeping it down, it's being kept down by active suppression of market forces.
>Do you want to know why so many of these initiatives fall apart? Because they get sold as pipe dreams.
Are you saying that the Navitus Bay proposal was a pipe dream?
>So sell it that way. Don't perpetuate the myth that we are "just about there"
Price per kwh-wise, we are already there: http://www.independent.co.uk/environment/wind-power-now-the-...
And you are once again picking a single metric to compare against (seriously, read the other branch where there is a great discussion that breaks things down a lot better with respect to an island off the coast of Scotland).
Price per kilowatt-hr is one metric that is worth considering. So is kw-hr per square mile, installation costs, maintenance costs, and many others. Not to mention that a lot of those metrics assume optimal conditions which might only exist for a portion of a given day (or year...). The reason why filthy sources (oil and coal) and comparatively clean (nuclear) energy are used is that they are consistent. It doesn't matter if it is a bright summer day, a cold and windy night, or just a dreary morning: They make the same amount of energy per unit resource (mostly. There are actually a lot of caveats).
But, as mentioned, they are a lot harder to fine tune. And they result in a dependence on expensive resources and are bad for the environment (nuclear isn't AS bad, but it is still pretty crap). That is where clean sources like wind and solar come into play for the vast majority of the planet. We can drastically lower our dependence on dirty sources by using clean sources to supplement and wean us off of dirty energy.
But I guess I am not ideologically pure enough for you (or, at least, the small snippets of my posts aren't).
The UK is surprisingly far north. It's always surprising to me what North American places line up with European ones. Luckily for northern Europe, they have lots of other renewable resources to make up for the lack of sunshine.
I think possibly your opinion on Solar is a bit too UK-centric, since it's already very competitive in other locations, particularly anywhere that air-con is commonly used since that electric load is correlated with solar activity.
Sure it does, this is a tired old anti-solar trope that gets sillier every time it's repeated. UK does fine. Germany does fine.
There's definitely a lot of room for growth for solar, but it's not a panacea. I'm looking forward to what we can come up with.
Hawaii is at 6% solar power and climbing rapidly.
> The Tesla Energy batteries will supply a 52 MWh utility-scale energy storage system in order to help KIUC meet evening peak demand, which typically occurs between 5:00 pm and 10:00 pm... SolarCity said it would charge the utility 14.5 cents per kilowatt-hour for power from the batteries in a 20-year arrangement
[1] https://cleantechnica.com/2016/02/19/solarcity-deploy-tesla-...
I hope they can pour money into technology which generates power from the rain[1].
As with everything the new technology starts out with low power. But my hope is that they increase that and you can generate energy all year round. Even at night!
[1] https://www.engadget.com/2016/04/11/solar-cell-generates-pow...
I wonder about the ecological footprint of the batteries though.
As far as mining, I think the biggest issues as far as cost go are getting Cobalt, which is primarily only found in the DR Congos', and then in Tesla's case, finding more Lithium in North America.
I'm sure in a ~5 years or so, Tesla will create a massive battery recycling program as well to start bringing in those Tesla batteries on cars from the early models.
Tesla's CTO is giving the battery packs a 10-15 year minimum service life.
> I'm sure in a ~5 years or so, Tesla will create a massive battery recycling program as well to start bringing in those Tesla batteries on cars from the early models.
Tesla plans a recycling line at the Gigafactory. Old batteries in, new packs out.
Neither of these assumptions is apply to grid-scale storage. For (2), you can install 30% new capacity and keep the old batteries in service. And for (1), the size of the battery storage is dictated by wanting to last 3 cloudy days... which rarely happens. So you might only cycle 1/3 of the batteries on an average day.
In reality, with somewhat deep discharges, the number is actually closer to 600-700, before experiencing significant capacity losses of ~15-20%.
At 2000 cycles, I'd imagine the capacity to be somewhere in the range of 50% of initial. Now that doesn't matter for utility scale, because you can easily keep that 50% pack in operation, as long as your total capacity stays the same (adding new packs), but for smaller scale, it's quite significant.
Look up Nissan Leaf range degradation and you'll see what I mean.
There is an estimated 2.55 × 10^10 kg potentially economically extractable lithium available on the Earth. At current extraction rates that's "gone" in 42 years. Fortunately, lithium is recyclable.
But Earth itself, no, your figures are way off. There is 2.3 * 10^14 kg in seawater alone.
Here's an excellent discussion with sourced facts and figures http://large.stanford.edu/courses/2010/ph240/eason2/
There are 14,000,000 tonnes of identified reserves. There may be more, we just haven't identified them yet.
Estimates for the Earth's crustal content range between 20 ppm and 70 ppm. Using 20 ppm and the mass of the Earth's crust being more than 2 * 10^19 tonnes, it would be (20/10^6) * (2*10^19) = 400,000,000,000,000 tonnes of Li.
So although we'll only ever be able to mine a small fraction of that, I still think it's safe to assume that we are not capped at 14 million tonnes.
[1] https://www.greentechmedia.com/articles/read/Why-Lithium-Isn...
[2] https://en.wikipedia.org/wiki/Lithium
[3] http://www.tandfonline.com/doi/abs/10.1080/01496398608056148
edit: looks like Oʻahu is getting flywheels: http://amberkinetics.com/amber-kinetics-and-hawaiian-electri...
It's too bad Tesla seems all-in on batteries even for large-scale storage projects.
SpaceX is doing the same: use one rocket motor on booster and upper stage, and mass produce it. In contrast Ariane uses three different motors on one rocket.
The additional benefits of batteries over flywheels however is that utility-scale energy storage can be achieved with a wide range of battery quality. What I mean by that is that say, for example, a batch of batteries doesn't pass QC to make it into the Tesla cars by virtue of having only 85% of their desired capacity. They can still be used in energy storage facilities.
Same goes for used battery packs from Teslas that have degraded to 70-80% of their original capacity over the years. I surmise it's quite more efficient to use these packs for grid storage than to recycle them right away. Space is probably not a huge constraint for them, so it's not a big deal to use packs that operate in the lower capacity ranges.
Think of it as a big energy storage cloud like Backblaze's storage pods. They mix and match consumer grade hardware, but because of scale and redundancy, they can get away with it and still provide reliable storage.
Same goes for energy.
I'm not quite sure what the scales are for flywheel manufacturers compared to Tesla's gigafactory, but they're probably at least an order of magnitude smaller, plus flywheels generally can't be used as the main source of power in cars or portable electronics, while Li Ion cells can.
http://fortune.com/2016/06/22/bmw-energy-storage/
In the case of that Island I assume what they need is that over longer timeframes they have enough sun and can store the oversupply of electricity for a relatively long time, because the occassions when there isn't enough sun are rare.
Flywheels with air-bound rotors on mechanical bearings do, flywheels with vacuum-bound rotors on magnetic bearings don't as most of the losses are frictional.
If you have batteries, they can come online as fast as a flywheel.
This article talks about the issues a bit: http://www.zdnet.com/article/does-flywheel-have-a-future-in-...
One of the toughest things to overcome is that lithium ion batteries have a limited lifespan (although it's improving) and the cost for that life span compared to alternatives is pretty high, so the economics aren't great. Yet.
The environmental hazards, both in manufacturing and disposal, are not insignificant either[1].
With all that said, li-ion represents our best bet for future tech advances that have minimal environmental impact, especially for space travel.
Eventually. (But if I was a VC, I'd be investing in cleaner and more efficient ways to utilize petrochemicals in the near/mid term.. maybe looking at non-burning tech; whatever happened to fuel cells?)
1. https://en.wikipedia.org/wiki/Lithium-ion_battery#Environmen...
Toyota is actually coming out with a hydrogen fuel cell car: https://ssl.toyota.com/mirai/
Hydrogen is looking like a dead duck, at least as an automotive fuel. The Mirai costs about the same as a mid-range Tesla Model S. I know which I'd rather own.
PS: This also simplifies the problem to: Can you make and store hydrogen for a lower cost than natural gas.
That is an important consideration, but on a national level it may still be useful as redundant capacity. If your hydrogen tanks are fill up over months when production is vastly above demand, and only used in very rare situations then it might still be viable. At that point it's more a question of economics then thermodynamics.
However, the standby generators which use this hydrogen are a more direct comparison in cost and efficiency terms.
I suspect this is one of the reasons the powerwall makes so much sense for Tesla. The battery comes out of a car and then they re-sell it to go into somebodies house.
There is a start-up in Melbourne working on this model as well. http://www.relectrify.com/