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Is Storage Necessary For Renewable Energy?
mdsolar writes Physicist and energy expert Amory Lovins, chief scientist at The Rocky Mountain Institute, recently released a video in which he claims that renewable energy can meet all of our energy needs without the need for a fossil fuel or nuclear baseload generation. There's nothing unusual about that — many people have made that claim — but he also suggests that this can be done without a lot of grid-level storage. Instead, Lovins describes a "choreography" between supply and demand, using predictive computer models models to anticipate production and consumption, and intelligent routing to deliver power where it's needed. This "energy dance," combined with advances in energy efficiency, will allow us to meet all of our energy needs without sacrificing reliability.
This guy is clearly no energy expert. He should have consulted an electrical engineer familiar with grid behavior and transmission & distribution engineering before creating this over-simplified explanation. He completely ignores the importance of local load differences, and seems to assume there is a loss-less, instantaneous transfer of energy across the national grid, both transmission and distribution channels, with no limitations.
He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.
Its nice to completely ignore realities like overall cost. Its nice to not realize that industrial areas have a significantly different profile than urban areas, and that rural areas are vastly different. Its nice to call yourself and energy expert and get submitted to slashdot by those that believe you just because they want to, or because you fall in line with their agenda.
Credible experts are people who understand what they know, and what they don't know.
This is about as valid as the claim that "the wind always blows somewhere". Actual power generation data shows that weather is a very large scale phenomenon and the wind most definitely slows to a tiny fraction of its average power over an entire continent.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
The logical conclusion of this approach is automatic energy micro-auctions where kilowatt-hours are priced by demand, and internet-of-things style devices in air-conditioners and toasters compete to run for the 'best price'.
And when a sustainable per capita energy level can no longer be maintained by an increasing energy supply, the population will inevitably be cooked/frozen down to the appropriate size by unaffordable energy rates. Fun times.
Never worked as an academic physicist, never even completed a degree apparently.
Never worked in the power industry.
Never manufactured EE Equipment.
Nevertheless knows how to power the world?
-- Mike Greaves
http://www.theecoreport.com/gr...
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
In a nutshell, they need OSPF for energy transmission.
Just in time (JIT) doesn't work when one human understands the system and wants to leverage its dysfunction for bargaining power. Ask GM. When they want to negotiate and a small strike in one supplier can shut down their entire production?
The inefficiency of human ability to cooperate and resolve conflicts takes this, to some degree, off the table.
Sounds like what people did in the past, harvest the grain, dry it in the late summer warmth, mill it with the autumn winds, store the embodied energy in a bag.
So ignorant.
He probably doesn't even understand Power Factor -- let alone any real complexities in electrical generation and distribution.
He seems like a guy who added up all generation and all consumption, said that those numbers are essentially equal, meaning that this is just a question of distributing the power to where it's needed. It it were only so simple.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Its not that we WANT TO or SHOULD create this sort of energy distribution system, but just that we COULD in theory do so. It seems to me that such a system would be very much always on the hairy edge of crashing just by its very nature, but I wouldn't rule out the possibility in the future at some point, and it might make economic sense too, who knows? I really doubt we'll ever even approach this in any of our lifetimes though.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
We solved this problem once before - with fossil fuels. The answer is simply to have more capacity on hand than demand. We can do the exact same thing with alternative energy.
The difference is only that alternative energy doesn't have an "off" button, so we simply have to assume that, given a source of alternative energy, EG: a windmill, that we won't necessarily use all of its capacity. If we built gobs and gobs of windmills and solar panels, and installed them in such a way that not all their potential output is used all the time, we have a stable power grid.
The only difference is that the "off" button has to work differently. EG: a solar panel installation could dump unused power to a heating element or something. If power companies were smart enough to "get out in front" of this problem, they'd switch to the business of transporting power, which includes managing demand.
Unfortunately, power companies are run by myopic trolls, so I'm not expecting this business transition to go smoothly.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
... For coal power plants that are backstopping the renewable system. That fact is at odds with his statements. They are backstopping their renewable program with coal power plants... not choreography.
The problem with this idea is that the renewable systems often will not produce enough PERIOD. Not because they can't but because environmental conditions at that exact time mean the power is not there. If the wind doesn't blow and the sun is down... where is your power coming from? Now you could say "if you make the grid big enough, there will be somewhere that has sun and wind." Fine. But that is going to mean transporting power thousands of miles in some cases which means you're going to lose a fair amount to transmission. And even then the idea is pretty dubious on that scale.
I would argue that we need one of two things.
1. A break through in storage.
2. Reliable power generation to backstop the system.
What is more, wind and solar are not actually this cheap... they're only that cheap WITH subsidies. And it the growth of these subsidies that is largely pushing the prices at this point.
Here someone says "oil is subsidized too!"... yeah but not to the same relative extent. In absolute terms oil might get the same amount of money but its a vastly larger industry so the point doesn't really mean anything.
Anyway, I'm not arguing in favor of oil. I'd love for everything to go all electric. BUT we need to not cripple ourselves in the process.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
Like file downloads vs. interactive sessions, some power loads just need a long-term average and can be adjusted in time, without noticable impact, to shave peaks and get a closer match to generation - even if some of the generation, itself, is uncontrollably varying.
In fact, this is already being done. A prime example is in California, where a large part of the load is pumping of irrigation and drinking water. California utilities get away with far less "peaking generation" than they'd otherwise need by pumping the water mostly at off-peak hours. Cost: Bigger pumps, waterways (and in some cases "forebay" buffer reservoirs, below the main reservoir) than would be needed if the water were pumped continuously. This is practical because it was cheaper to upsize the water system than build and run the extra peaking plants. (Also: The forebay-to-reservoir pump generates when water is drawn down. It can also be run as a peaking generator, moving reserevoir water down to the forebay during peak load hours.) Similar things can be (and are being) done with industrial processes - such as aluminum smelters.
But there's a limit to load flexibility. Sure you can delay starting your refrigerator, freezer, and air conditioning for a few minutes (or start a little early, opportunistically), to twiddle the load. But you can't use such tweaks to adjust for an hours-long mismatch, such as the evening peak, or an incoming warm front leading to calm air and overcast skies on a chunk-of-the-continent basis. Try it, and your food spoils and your air conditioner (or heat-pump heating system) might as well be broken, or too small for your living area. Sure you can tweak factory load some. But do it too much and you reduce the production of billion-dollar factory complexes and workers who are still getting paid full rate.
Renewable energy actually helps - because its large-scale variations are driven by some of the same phenomena that affect heating and air conditioning loads. More wind means more heating and air conditioning load due to more heat transfer through building insulation. More sun means more air conditioning. Solar peaks in the day and wind in the evening (due to winds driven by the "lake effect" on a subcontinental scale), so a mix of them is a good match for the daily peak. But it's nowhere near "tweak to match generation and load without waste".
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
He needs more computer models models so he can finally realize he is full of shit.
The power grid does not work that way. Probably not in any country in fact.
They require constant balancing to prevent the thing from collapsing in on itself.
Energy storage helps this considerably because it allows for you to quickly put energy in to the grid, whereas it would have normally been a case of some people throwing more fuel in to the fire to balance it out, which can, and almost always did, end up being wasteful.
It still is even now because energy storage is expensive on the scales required for the actual power grids in a country.
The person or persons that create the cheapest power storage will make a stupid amount of money. (despite the fact that it is cheap!)
We badly need good energy storage. Badly.
Equally we also need better batteries. It is holding back everything. We'll never have decent "desktop replacements" without a decent battery for it.
Yes, but doing so requires one very significant change to how we currently distribute power across the planet.
We need nothing less than a planet-wide superconducting power backbone (preferably with some significant degree of redundancy). Until we have that, we have no alternative but to have a few days' worth of local buffering capacity.
Now, once we get over the BS "national security" implications of such an impressive infrastructure project, the yes, we just need enough worldwide solar/wind/tidal capacity to meet the planet's power needs at any given point in time. But until then, the idea counts as a non-starter. We can't just have local rolling blackouts based on a day or two's bad weather.
Energy transport line losses across 1/2 continent won't do any good and there is no rolling sunshine across this continent, not even talking about "rolling" winds and tides always available.
So, what's the real game here with getting the prudent and necessary things done?
Arguments are researched for impact - example: The argument "jobs endangered" comes up again and again, if there is a demand for change. Any decision-maker does the right thing s/he is paid for....
Doing you homework is what makes you an expert. Pretty clearly, Lovins has done his as you would know if you had done yours. http://www.rmi.org/RFGraph-pre...
This idea has the lowest overall cost of four possible scenarios to cut carbon dioxide emissions 80% by 2050. So, invest in storage if you like. But it is unclear you'll have customers.
Keep saving those AA's. Your gonna need them.
Heh, I laughed at this because one of my ideas is to use old but still viable EV batteries as grid storage devices, and the Model S, with the biggest batteries, uses the Lithium-Ion equivalent of a AA.
If you figure that the battery is retired from the car at 70% capacity and kept as a grid device until it's around 40% capacity this would give you massive storage capacity if only 10% of people drive a Tesla type car.
Of course, this would be a 30 year solution - 5-10 years for the batteries to degrade to the point they're no longer useful in a car, plus 20 years for EVs to actually penetrate the market enough to provide enough batteries.
I don't read AC A human right
If peak PV power is mid-day, then do energy-intensive tasks mid-day, if there starts to be a significant amount of PV energy available.
Certainly some appliances, like clothes washers, dish washers, and clothes dryers could be programmed and scheduled for mid-day use, while you were at work.
Uh, Linux geek since 1999.
Perhaps you should look over this NREL study. http://www.nrel.gov/analysis/r... The things you worry about seem pretty well worked out there.
"Unfortunately, power companies are run by myopic trolls..."
The complete truth is, the ones run totally as IOUs, as opposed to co-ops, are run by myopic trolls.
This is why running utilities as a private business is a LOUSY idea.
As an aside, the idea of distributing energy from "green" energy sources to where it is needed would only work on a global basis. You might want to recheck the current world political situation; it is not ready for any global solutions, yet.
I'd argue that staggering appliances as described would be a form of storage anyways. For the most part we're talking about thermal storage here - hot water heaters, house temperature, etc...
It's quite possible to build a house that will remain comfortable with minimal power expenditure in most areas, but this is extremely expensive in terms of money and resources. A halfway point would be to use construction techniques involving having lots of mass inside the insulation to help maintain temperatures even while the HVAC system is offline. But at that point you're putting thermal storage systems into all the homes, even if it's dual purpose.
I don't read AC A human right
Have an odd sense of humor.
You can see why nuclear power can't compete: http://www.rmi.org/Knowledge-C...
Tesla's replacement 85kwh car battery comes to $140 per kWh based on the wiki numbers, other companies are joining the market, one said they can produce at $160 per kWh of storage. There is no reason why these batteries can't be married with renewables to take 90%+ of the market in the coming years. There is no reason to believe these prices won't continue to drop.
So why not grid level storage, this video shows it can be very useful:
Fully Charged - Electrical energy storage and its place in a low carbon future.
It looks like renewables + storage will be very feasible in most of the world within the next decade or two. The video I linked shows it is being trialled in the UK right now.
Nuclear is dead, coal and gas are next, the writing is on the wall. http://solarcellcentral.com/im...
Waterfox - a Firefox fork with legacy extension support, security updates and better privacy by default.
In another analysis I read a point made was a hidden issue is the need to keep legacy coal and nuclear plants running because they aren't flexible. Wind and solar output can be turned down all the way to zero. But nuke plants you can't turn down more than 50% or so. So you have a problem, wind turbines and solar panels cost nothing to run. But because you can turn off a nuke plant, you have to pay the wind farmers and an solar installation not to produce power.
My take then is a mixed grid is problematic. A grid that uses mostly renuables will have times when you have excess capacity. Really what that means is you have periods when power is extraordinarily 'cheap' that is an big opportunity for some players. People talk about the need for storage without getting that smelting aluminum is another way you can store power. You don't get it back as electricity, you get it back as aluminum ingots. Note that the aluminum and the energy expenditure is represents is static, doesn't matter what time of day you made the stuff.
You don't like institute research, you don't like university research. Basically you are just like a climate change denier.
It's not just economist talk, actually. It's a waste in that it's an added expense with no benefit other than fitting to this crazy variable power scheme. If there's demand for 10K widgets a day, then ideally the factory buys 10 Widget Press 1000 models that can turn out 1000 a day each and runs them full blast. Under a variable power scheme, they need to buy 15 machines to variably run production between 5K and 15K a day for an average of 10K. The additional cost of 5 machines isn't free, not is the ongoing maintenance for them. Maintenance crews have to be there whether 1 machine or 15 are running, so there's no significant cost difference. This doesn't even begin to address the issue of attempting to employ workers under a scheme where some of them only make enough money to live on when it's windy.
I think the biggest mistake of the video, is when Lovins says that renewables are no different from baseload power plants, because baseload plants are down some fraction of the time also. He claims that power companies already compensate for downtime of baseload power plants by just having a few extra power plants. He claims that the same thing could be done with renewables.
That's just all wrong, in my opinion. It's a statistical error. Although baseload power plants are down 10-20% of the time, they are down at random. The downtime of any one plant is not correlated with the downtime of any other. As a result, if you have enough plants, then 10-20% of power generation is offline at any given time, as a result of the law of large numbers. That can be compensated for by building a few extra power plants.
With renewables, their downtime is not random. Their downtime is correlated with that of the other plants. For example, when the sun goes down, all solar panels stop working at the same time in a geographic region. Also, when the wind stops blowing (which can happen over a wide area), all windmills in that region will stop working at the same time. This is a much bigger problem than randomly distributed downtime.
If solar panels had randomly distributed downtime, and were as likely to generate power during winter nights as during summer days, then no storage would be required. We could just build more solar panels. This is because the randomly distributed periods of downtime of the solar panels would "cancel out" each other. However, it does not help to build more solar panels for the night time.
That is why renewables require storage.
The American Physical Society, http://www.aps.org/units/fps/m... Association of Energy Engineers http://www.aeecenter.org/i4a/p... and the Annual Appalachian Energy Summit http://www.news.appstate.edu/2... all seem happy to have Lovins as a Keynote speaker. Guess claims he is not an expert are ignored by these groups.
There still is one in the land of the free? This must be a communist conspiracy! Putin - he is doing his dirty deeds here!
Lets say the grid operator detects an impending mismatch between supply and demand and they want me to shut down my refrigerator. So now I have to size my refrigerator such that it will 'carry through' such an outage without my food spoiling. That's just another form of storage. But now you've come up with a sneaky way for me to pay for it. And subsidize the renewable energy producers.
Will I get a tax credit for my extra large freezer? My oversized hot water tank? The extra capacity air conditioning unit I put in?
Have gnu, will travel.
Who said the same thing 100 yrs ago (about a wireless "grid") only to be faced with the reality that energy companies are in business to make money, not supply electricity (kind of hard to do when any good hacker can tap into it freely). A fully wireless "grid" could only work in a communist/socialist society where "the people" are the suppliers.
One thing solar can do beautifully is to create clean fresh water from seawater whenever the sun shines.
There is a large potential for energy demand management given the increasing adoption of EVs. Electric companies can charge a variable rate for EV energy. Then people can program their EV to charge at certain rate given the instantaneous rate of electricity.
Some renewables have inherent storage, and the power usage of some very power-hungry industries can be varied easily, eliminating a huge portion of the storage that would otherwise be needed.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
Both of your examples already store energy and turn on and off to modify the stored energy. Why? Your fridge would not enjoy turning the motor on and off several times a minute, or running below a certain speed. Your heater probably also functions in bursts, since it's easier to turn a heating element to full for a short time than allow for it to run at variable power. So, they have thresholds where they'll turn on and off at different temperatures; turn on at one end of the acceptable range, and turn off at the other end.
It would take only a cheap, trivially simple circuit to allow them to function as load balancers to the grid, with negligible loss to performance. And certain industries, like aluminum or electrolysis, could do load balancing on a seasonal scale.
Before you complain about the costs involved with variable power usage, the reason people will do it is because there will be a financial investment. Many areas already allow you to buy power more cheaply depending on demand, so there's already a financial incentive to do this if it is worthwhile.
Finally about those tax breaks: Where's my tax break for living near to a polluting, carcinogenic, ugly, property devaluing coal power plant? Yeah, that's what I thought.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
Like the economics studies for solar that ignore insurance costs in areas where the mean time to a destructive event is less than the estimated useful lifespan of the modules.
I support the idea of renewable energy, and in particular self sufficiency, but I don't like the idea of financing other people's fantasies and political agendas.
The "We don't need no sink'n storage!" propaganda is the result of the realisation that adding storage to the economics makes solar much more expensive and less competitive in many scenarios.
> the minimum output of variable sources like wind. If you have enough turbines the wind is always blowing somewhere, and the overall output of the entire fleet never drops below some predictable level.
Not at all true, but it doesn't need to be.
The energy in a fluid , such as air / wind, is proportional to the velocity SQUARED. In other words, if a 10 MPH wind has 100 units of energy, a 30 MPH wind has 625 units. A light breeze of 5 MPH, just 25 units. 40 MPH, 1600 units.
So suppose you build a turbine with a design speed of 25 MPH (625 units). You don't want it to fall apart in higher winds, so the blades, bearings etc need to be big and heavy enough to handle over 1,000 units. That means you'll have friction and other losses of about 25 units. Notice the loss is the same as 5 MPH of wind - you get zero energy production at 5 MPH. At 10 MPH, energy output is negligible. At much above the design speed, the force on the structure quickly becomes much higher than the 625 it's designed for, so the blades are rotated and such to work AGAINST the wind, to avoid having the turbine tower blown over or spin apart. These facts combine to mean turbines produce a useful amount of power only within a narrow range of wind speeds. Unfortunately, the rule power = velocity squared is a fundamental fact of physics. You can't change that by inventing a new type of battery chemistry or something.
If you look at a radar map of the US, you'll see one or two weather systems covering nearly a million square miles moving across the country. Missouri may be on the north end of a system while the southern wind of the system is in central Texas. That's pretty typical that the radar will show one or two systems for the whole country. So it's simply not true that the country as a whole always has "average" weather, that the wind is always 25 over much of the country. The fact is, a windy system will move across the country one week, then the next week heat wave will tour the country.
If you wanted to use wind as your "stable" primary energy source, you'd need a week of storage.
Fortunately not all energy needs to be a stable primary supply. If wind produces good power 10% of the time, you can reduce the use of natural gas generators 10% of the time. That's a good thing! If solar heating heats just your hot water, just 30% of the time, that's a lot of natural gas that doesn't need to be burned.
Since they are often idealists, it's not surprising that advocates of renewable energy always have their eye on renewables as a complete replacement for primary electrical generation, but it's sad because it means we've almost completely missed some great opportunities to make a big difference. Th syn is REALLY good at heating things up. If you've left water in your garden hose in the summer, you know making an effective solar water heater is dead simple - so simple most of us have done it on accident. Yet, most of us heat our water by burning fossil fuels. Why? Because we've ignored the obvious, simple, effective wins as we focus on the holy grail. We've spent tens of billions of dollars on solar electric and a workable solution is always five years and two billion dollars away. For half that money, we could have converted all homes to solar water heating AND mostly solved world hunger with the billions left over.
I edited my post from 25 to 30 MPH, but didn't edit the square. 30 would of course be 900 units in that example.
He's insane. Choreographing that kind of balance across a national power network would be prone to instability and likely vulnerable to attack/accidental cascade failures. Virtually every heavy load device and a lot of lower load devices would need to be remotely controllable, that communications system would need to be highly secure, extremely reliable and not too imposing on customers. Load balancing definitely has a place in both residential & industrial areas, but there needs to be a significant storage/load redundancy built into the system as well to handle unexpected peaks and valleys in demand inherent to a real world electrical grid.
Has anyone called bullshit on this yet? Ok, here's a few little things: since we can't do weather prediction beyond a week, tell me in 30 days when a big winter storm is going to blow in. Or a hurricane. Or a tornado. Heck, even a heavy thunderstorm. Or a heat wave. All of these will affect the power grid. And they are unpredictable. They also affect the fuel grid, just like the middle east affects oil prices. Tell me when there is going to be another major disruption. Hello? If you want a constant supply from wind farms, have the farm pump water up into a reservoir (like into a million gallon tank), then draw power from that tank with 100 feet of head pressure onto a turbine on demand. There is no magic dance, and no algorithm comes with a crystal ball.
reading through above post I really get the impression that posters love their grid and want it "to just work". ... unlimited. all the before mentioned sources were acctually available when the dinosaurs roamed the earth and still work today, and this is not because the dinosaurs didnt use up all the sun and wind and waves and heat of the earth. ... more oil using machines and then euphemistically calling the disappeared and nonreplaceable oil not a debt but a profit!
also I get the impression that many dont have any experience with grid-tied solar at all and think it is something that "breaks the grid" and is akin to satan worship.
there is really one undeniable fact: solar and wind and tidal and geothermal are for all pratical matters
easy oil will run out and so will gas. coal will stick around and so will nuclear. but they do not have the attribute of "unlimited". if we continue on this path our generation might not see the end of it but there is no use denying that this 8 lane smooth highway will peter out to a crummy muddy potholed path....in time.
you can bet that it will have some nasty surprises (or not so surprising) along the way. war?
further real sustainable exponential growth which wallstreet et al. all like can only be continued if we stop trying to profit from "energy production", harness the unlimited sources and start doing real things.
I dont consider pumping a oil well dry to power a factory that makes
as it stands now destruction and making natural resources dissapear is called a profit in ledger books. wow. just wow.
I would suggest taking a look at the 8760-hour output of the NREL PV Watts program; it is enlightening. For me, if I sized a PV array at 150% capacity (best-day production vs average demand), I would need 80 hours of generator backup per year if my battery were sized for 3-days demand. If I have 7-days, I would only need a generator for 4 hours per year of generator.
The bottom line is that you need substantial excess capacity and a huge geographic diversity to be able to get by on renewables alone. Think 400% or so. That is incredibly inefficient.
It took no more than two minutes and 43 seconds into the video and the half truth come flying. Yes, Germany my deliver 25% from renewables without bulk storage. They do it by adding dispatchable sources, namely coal power plants.
so many other "experts" at think-tanks on both the left and the right who exist to [1] collect donations from the far right or the far left (RMI happens to be far-left) and [2] arm left or right wing politicians with "studies" and additional "expert" speakers and blocks of supporters (at no cost to any political campaign) which "prove" whatever the politician's rich backers want (effectively a laundering of campaign money). This is NOT a plan for a powergrid so much as it is a plan for a political argument to try to help politicians facing a surly electorate.
Don't people here on Slashdot consider the source? This is a left-leaning "green" outfit pushing a book that pretends to show that "Hope and Change" will work, in a hypothetical future, if certain imagniary stuff is built and run by perfect unbiased apolitical experts --- in place of actual people who actually provide real electrical power to homes and businesses and Hospitals TODAY. The startling thing is how much of that stuff RMI is pushing is projections and wishful-thinking of decades from now (with implied certainties) ... these left-wing (and their opposites an the far right) usually do a better job of pretending the materials are more tethered to reality.
We've all met many teenagers who have all sorts of perfect plans for ways to do things "better" than the way they are done now - none of these teen experts even understands how and why the things they THINK are so bad actually WORK (or why they work that way), nor do they have any actual usable blueprints for replacement systems etc. They are just pontificating on things they do not understand with a level of technical understanding that comes from pop-up books. Things seem simple to them because they are in Rumsfeld's world of "unknown unknowns" (i.e. they do not know what they do not know). THIS is the sort of person most-easily pursuaded by this report - the sort of person who thought putting a "community organizer", who'd never done anything productive in his life and had no understanding of HOW THINGS WORK (not technical things, not military things, not economic things, NOTHING but "crowd organizing"), into the White House was a good idea. Yeah, that's a slam on Obama and Obamabots and that mindset, but NOT on all Democrats/liberals ... ALL of America's previous successful Presidents (without regard to party) had previous careers doing SOMETHING productive and/or creative and real-world experience running SOMETHING.
All RMI appears to be doing here is attempting to give "greens" a rational-sounding escape hatch for what every sane person who understands the power grid knows is the achilles heel of all this "renewables" hype - the FACT that windmills and solar etc cannot provide a stable grid without some massive energy storage system which is completely unaffordable and unworkable. All the grid stability today is provided by fossil fuels and nuclear, both of which the know-nothings pretend can easily be eliminated or replaced (in this case aided by the (false) pretense that inserting more top-down control over the consumers of power will help the unworkable scheme work) The RMI plan (like all the plans I have heard teenagers propose for easily fixing all the world's problems) does not actually have to work... it just has to look workable to the ignorant so that it can be used in political arguments to influence the dumbest part of the electorate (the so-called "undecideds" who often go to the polls not even knowing the candidates or issues). Unlike the people currently running America's current power grid, RMI will not face millions of angry people and their elected officials if their product does not provide affordable, reliable, stable power. This is no different from all the left-leaning health-oriented think tanks that are churning out papers about how wonderful the Affordable Care Act is... (talking points for November's elections that ignore any contrary information). Papers and books like this are
You guys speaking ad nauseum of the almighty air conditioner would do yourselves a favor if you would instead pick an example that is not THE textbook example of an appliance whose consumption peaks are extremely well correlated with readily available renewable power.
If only there was someone magical unicorn renewable energy source that could be installed on your roof and generate power during exactly those hours when you need to use your AC....
They're all anti-nuke, "green" energy, global warming, "let's all power the world on unicorn farts"-style daydreams, etc.
"Peer reviewed" is entirely meaningless if an author and his peers are ideological and in agreement. The total politicization of climate change and the exposure of the rigging of the peer veview process in that arena have driven a stake through the heart of the "peer reviewed" argument. Any "paper" published by the guy running that "creation museum" would pass a "peer review" by the people he would pass it to...
OMG terrahrists! Won't somebody think of the children?
Other posts have covered most of why this (interesting) idea won't work. Here's another - grids and grid management systems around the world are already struggling to cope with the current setup, mainly due to years of under-investment.
Feed-in problems are not trivial; (causing more grid management issues), "green" sources of energy are expensive and tend to be in the wrong places...
I'm all for "alternative" energy, but is everyone prepared to invest the bazillions required to do it properly, and live with the massive price increases that would require?
Nope.
Since when does being undecided make you dumber than a decided republican?
Why does everyone seem to think that the only way to store electricity is in a battery?
Flywheels are a thing. They might not scale up as effectively but they're definitely an option. But really, anything that stores electrical energy as potential energy will work.
But there's a better solution - hydropower storage.
Near where I live, there's a nice artificial lake made by a hydroelectric dam. Not too far away is a big nuclear power plant. During the night, power demand is very low, but nuclear reactors don't throttle down very well so there's an excess. You know what they do with that?
They pump water upstream, back into the reservoir, thus storing that electricity for when the demand is high the next day and they let it drop back down. That artificial lake basically gets artificial tides - every day the water level drops, and every night it rises back up.
Guess what? Most renewables are also at their highest output during the day. Why not use clean, renewable storage for this clean, renewable energy? Why does everyone seem to assume the choices are "nasty expensive chemical batteries" or "zero storage requiring demand-side hacks to keep things from falling apart"?
... is being pushed mostly by snake-oil salesman and frauds looking for Government handouts.
No, Virginia... just because the wind is blowing in Boise it doesn't mean you no longer need power generation for factories in Los Angeles.
Renewables are great. Passive energy-begging is wonderful to reduce the load. You still need generation.
Fuck off with the scaremongering and lies and lets prop up some goddamn nuclear plants already.
Exactly. This is probably just some sort of political "think tank" with an agenda.
Here is the simplified answer:
A) No, storage is not needed, if you do not plan to replace base load generation but rather use renewable sources to augment your energy mix.
B) Yes, storage is needed if you plan to replace base load generation with renewable, however there is not enough "storage" to ever come close to doing this in any meaningful way unless someone develops some sort of magical storage battery that isn't limited to appropriate locations for hydro storage and generation.
Too many people are enamored with the idea that renewable energy is the magic bullet to solve all our energy needs. Maybe someday, but not today, nor anytime in the foreseeable future (barring as I said some sort of magical storage device).
There is what our large systems will produce all the time if they are to be run with maximum efficiency, and we call that baseload, but there's fuck all that requires baseload other than we've had sodding great big generators running at 100% for as constantly as possible.
The fact there IS NO BASELOAD is shown by how cheap nighttime electric is. It is over generated and unsellable,so it has to be dumped on the market.
Distribution grids already have mechanisms to handle loss of generation like: Lowering voltage, asking large customers with back generation to go to the backup, Turning on the faststart Gas Turbines, ramping up the generators online to max output, bringing offline generators online (takes a while but it is an option).
Demand can also be controlled. Currently demand is controlled by asking customers to lower their demand, By lowering voltage. Some utilities are looking into being able to remotely control customers high demand appliances and HVAC systems. They can lower demand by turning down or turning off heating, air-conditioning, water-heater, and maybe even the fridge.
A single home isn't a very good proxy for a regional or even national scale grid.
With your house example, the only options are solar and generator. In reality you would have more than these two options. For example, add wind to the mix. You can argue that it's not 100% but it will cover a lot of run time at night, saving you battery capacity and reducing the required over-sizing of your PV system. Perhaps instead of 400% oversizing on PV, you only need 200% PV+Wind oversize.
Now add in something else... biogas perhaps. That covers you a little bit more and you can again reduce your oversizing.
Now add geothermal, hydro, solar-thermal (which works at night), and you start to easily fill in the gaps.
The US had 1,153 billion watts of generating capacity as of 2011 (Nameplate ratings, spreadsheet) and used ~3,797 billion kilowatthours that year. Naively we can say that if all our powerplants ran at 100% nameplate capacity, we could generate an entire year's worth of electrical energy in just about 3300 hours, or about 4 months... giving us a roughly 300% oversize on our electrical generating capacity *now*.
The key, of course, is that none of those plants are operating 24/7/365, and rarely are any of them operating at peak capacity.
=Smidge=
This is being done at a study level today, in anticipation of a large hit of batteries coming in the next 3-5 years as the first wave of Volts need new cells.
You think wind turbines can only produce power in a narrow window of wind speeds they will commonly encounter while at the same time calling renewable energy advocates ignorant (and by implication identifying yourself as a renewable energy opponent)? That's a particularly virulent strain of Libertarianism that's infected your brain.
This concept applies to markets as well. If we reduce the demand for hydrocarbon energy by 30%, the hydrocarbon market might well fall apart. As it is, it can only operate in the current envelope it exists. Just like your turbine that is useless in 5mph wind, or another that falls apart at 30mph.
Fortunately markets are created and run by humans. They're a construct. We can change them unlike the laws of physics. There are people that make fuckloads of money off of the current market, however, so they'll resists very very very very hard to make sure that returnables don't destroy their current racket.
Switching to better energy will mean destroying the current energy market. Get ready for a fight.
> If we reduce the demand for hydrocarbon energy by 30%
For the last 2,000 years or so, the demand has just kept going up, lately at a pretty fast pace. Therefore I don't think a 30% reduction is too likely. If we did some reasonable steps, like solar HEATING rather than wasting all of our time and resources into trying to make the sun a source of electricity, we could get close stabilizing the demand, having the demand stop increasing.
I said proponents are often idealists. Do you not know the difference between idealist and ignorant? If not, you may in fact be ignorant.
If you'd care to become less ignorant, here's a good overview of the physical limits of turbines:
https://dspace.lasrworks.org/b...
> and by implication identifying yourself as a renewable energy opponent
Yep, THAT'S why I advocate renewable energy that works, like using the sun as a source of heat. You might have noticed, the sun is really good at making things hot.
Were I an opponent of deploying renewable energy, I'd encourage people to focus on renewable scams that can never work on a large scale, like pretending that the sun is a source of electricity rather than a source of heat.
Power is actually proportional to velocity cubed. Velocity squared is the amount of energy per unit mass, times the number of units of mass that go by per second (velocity again). This makes your point even stronger...
Except that there's points, especially with tornados that 'not destroyed completely' is not any better, such as when the repair costs exceed the cost of just building a new home of standard construction. For example, just consider the expense involved with a few broken windows letting in sleets of water.
I like the idea of energy efficient homes, I just know there are points where said homes are not fiscally efficient.
I don't read AC A human right
Power is actually proportional to velocity cubed. Velocity squared is the amount of energy per unit mass, times the number of units of mass that go by per second (velocity again). This makes your point even stronger...
Thanks for that. Yeah, velocity squared would be the right thing for the energy of an object, such as a car, correct? Or for a cubic yard of air. Also, higher velocity means more cubic yards flow past each minute, so that's the multiplier I forgot. Is that right?
So 25x25x25 = 15,625 but 10x10x10 = 1000.
Meaning, the power at 10 MPH is just 6% of rated capability at 25 MPH.
I actually thought the 10 MPH number in my initial post sounded a little high in comparison.
an 18650 has 10 watt/hrs of Juice - Often 3X of a 14500.. =aka. AA.
I modeled a quad-gen system with 4kW PV on 2-axis trackers, a 3kW wind turbine, 1kW micro-hydro, and a 2kW genset. Annual energy consumption was 7.5MWh. Batteries were sized at 25kWh; the micro-hydro could do 20kWh storage. I had some substantial demand-side flexibility due to a RO system that was sized to handle peak demand with 3 hours of operation per day, thermal storage, and a few other tricks. Peak demand was 5kW.
The PV System produced 86% of the needed power, and wind 12%. The micro-hydro was primarily backup, and was adequate for all but 6 hours per year when the generator was required. In practical use the generator would likely need to operate more when other components were out of service.
The point of this is that I needed 2x capacity vs peak demand, and 11x for average demand, even with tremendous flexibility in demand-side control. While the wind saves a few cycles on the battery per year, at least two thirds of the energy produced would be burnt up by the load dump. The microhydro was a waste and would never justify the cost; likely much more environmentally friendly to just get another generator.
The lowest capital cost solution for me would be a 6kW PV Tracker and a 65kWh battery, along with the 2kW genset, but I would be generating 30% more power than I could use most days. Running the numbers isn't that hard; even taking grid stability issues out of the equation it is clear that you are stuck with a substantial energy storage issue, either in the form of thermal or chemical.
What resources did you use to model these inputs? PVWatts I can understand for solar, but I'm not aware of any similar tools for wind and micro-hydro. Genuinely interested in what your data sources were.
Not that I'm yet convinced your model is applicable to a regional or national scale grid. Did you account for geographical diversity? Availability of these resources spread out over maybe 200-300 mile radius?
Also, peak demand of 5kW for 3 hours? My home has all electric appliances and I rarely, if ever, hit that... including the 3kW clothes dryer. This observation is neither here nor there, but that just strikes me as a high value.
To put things into perspective, I've been collecting minute-by-minute data for my own home's electrical usage (Got one of these things) and based on incomplete-at-the-time data it was looking like I could get away completely off-grid with a 6-7kW PV system and about 6kWH of storage. Less if I was smarter about how and when I used that power. Maybe your data doesn't have good enough resolution to really optimize the system.
=Smidge=
The PV Watts gives ambient temperature and wind speed data in the hourly CSV output, and I just created a formula to calculate available wind energy for the given wind speed and turbine efficiency. The microhydro was just a basic reserve calculation on my elevation change, reservoir volumes, and average monthly rainfall; my intent was to try and use it as a dump load as well, but it wasn't effective.
The project included a greenhouse, desalinization system, and I was cooling a thermal mass during the afternoon when I had available power. The desalinization system could run for 3 hours and generate 24 hours of water consumption, not 3 hours at peak load.
How many days are you planning for a battery? I found I didn't have many discretionary loads that could be deferred for more than 3 days which drove storage substantially when I wanted to limit generator run time; I needed it 80+ days per year with a 3-day battery.
There are likely some math errors on demand side (especially looking at installed HP for some motors rather than going to the trouble to calculate BHP), but the general results seem rational.
Sounds like you've got a much higher essential demand than what I figured on - desalinization?
Sorry for the delayed reply but I was re-running the numbers :)
When I was doing the calcs originally, I was really only interested in staving off power outages like we had with Sandy, which was about two weeks worth... not being completely off-grid. So focusing on hurricane season as a baseline, a 7kW system with 6kWh of storage would provide essentially unlimited off-grid capability from April through December *if* I managed my power consumption to essentials with just a little bit of creature comfort.
The winter months, however, result in a deep, DEEP deficit. I'd need 10kW of PV with 80 kWh of storage to be completely off-grid based on PVWatts data (with no power management). Of course, that's still relying only on Solar, and being completely off-grid was never the intention.
I don't pertain my own home is a good proxy for a regional or national grid, though ;)
=Smidge=
Nuclear is the only answer. Thorium is the only fuel. LFTR NOW!