Potential of Solar to Replace Fossil etc. Capacity Needed to do that

(the links to external sites are not selling anything :-) )
SolarByTheWatt.com has an interesting article - Can Solar Energy Completely Replace Fossil Fuel and Other Sources? - about capacity needed, solar installation cost and land area needed to install as much solar as to offset certain stages of electricity and other energy production like from oil and coal in the US and in the world.

Has any one seen other comparisons like that?

What is interesting is that to just replace the most critical ones like coal and oil does not look that expensive or demanding on land. It will take small part of the money spend on the stimulus package to achieve the first levels.


  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    nobody truly knows what power is needed because power needs change all of the time, usually upward.
    do i think solar will replace fossil fuels? no, but it can help tremendously along with other renewable sources. also know that you have to rethink your thoughts on land area needed as the land area most roofs take up is wasted anyway as far as solar goes. how about those telephone poles as they can fit a few pvs each? it is a misnomer by many that solar must be located all in one centralized spot like our present day generators in power plants are. in fact, as far as renewables go, that is a dumb idea to centralize them. i'm not saying small clusters is a dumb idea, but that renewable energy does not have to have one large generation area so solar farms do not have to exist to collect it. solar could free up loads from our present generation plants that they won't have need to produce, but it also lightens the strain and losses on our grid system as the renewable sources are closer to many of the loads than the main generators are.
    i don't know what kind of kool-aid you have been drinking to think that this administration or the next one or the one after that will make a dent in being able to pay for that much solar power for it is extremely expensive on the scales you are talking of to replace fossil fuels. know that it is very expensive anyway and that most of us are used to hearing political hype from our representatives not to mention some get rich quick companies taking advantage of people wanting to 'go green'. i believe that most of those dollars will be earmarked elsewhere or pocketed as governmental operating expenses so little will be realized as actual solar being implemented. they often show so many millions of dollars set aside for renewables every year in many states and the federal government that if it actually was all spent on renewables would make our heads spin and industry would not keep up with the demand. we do hope for the best and take whatever we can get as little as it is.
    note: this post is not a political statement, but is a realistic look at how inept our government is in most areas. even if they weren't, you would not realize the replacement of fossil fuels, at least not in mine or your lifetimes.
  • WindsunWindsun Solar Expert Posts: 1,164 ✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    The numbers there don't look all that far off, perhaps a bit optimistic as things like government waste, lawyer fees, graft, infrastucture etc were not factored in.

    Bottom line is, for any massive energy savings conservation is a better place to start.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    even if everybody started to conserve, which they should, in time due to population increases, the electrical needs will still shoot upward and electrical generation needs will follow that trend. i have seen the population go from in the 100+ million category to the 300+ million category we see now and it is increasing faster as time goes on.
    we are in agreement that if they actually spent it where it's supposed to go to that it would be vastly different.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    Just to expand a bit on a point Niel already made:
    Given the number of massive black-outs on the centralized grid system we currently use, decentralizing power might be a very good idea indeed. Less likely to fall to bad weather or attack. Surely there is some sort of economic benefit to not having every city on the East coast blacked out because of a cascade failure after one breaker trips in Buffalo, NY.

    As fossil fuels are becoming more expensive (particularly when you factor pollution costs in) solar is becoming less so due to design improvements and economies of scale as production goes up. That last part due largely to we pioneers who have, for whatever reason, bought the first equipment at premium prices.

    Roof-top installations may work for single family dwellings, but on apartment buildings there isn't enough roof-per-occupant to yield a very good return in that respect. And certainly it makes more sense to install solar in the sunniest places first!

    I wish I was in one of them! :cry:

    P.S.: Using the right type of energy for the job makes a difference too, as well as controlling waste. But I'd hate to see a lot more legislation regulating our lives, dictating what we can drive for instance. Make the choices available and educate people so they can make the correct decisions.
  • Bob McGovernBob McGovern Solar Expert Posts: 25
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    Re: distributed generation. It's worth noting that over half the electricity generated in the US is lost in the wires. Some estimates say 70%. If we can reduce median household consumption from 30-35 kWh/day to a realistic 12 kWh/day, which can be done with moderate capital outlay but minimal lifestyle impacts, and move toward a distributed grid we could quite feasibly reduce US demand by two-thirds to three quarters.

    Suddenly, renewables could make up a substantial portion of our energy portfolio. We're now aiming for 15%. Reduce consumption two thirds, and that same installed RE capacity would supply about half our power needs. For the balance, we could then pick and choose from 'boutique' energy sources, like 'clean coal' or natural gas or even nuclear, technologies that at present are hampered as they compete with dirty coal at 2.5 cents per kWh.

    Our mistake to date has been to think as electricity as a bulk commodity, like potatoes or gravel, rather than a precious one, like caviar or titanium. We make it cheap, distribute it under subsidized prices, and we shouldn't be surprised that consumers take it for granted and treat it carelessly. RE cannot supply a nation that treats electricity as an all-you-can-eat buffet.

    What if we cut domestic consumption by two thirds, enforced by a progressive billing structure in which unit cost tripled with every 12 kWh used. There would be a strong incentive to move your house or business into the lower rate class. Utilities would be allowed to pocket some of the difference; widespread conservation means they sell less product, but they can charge a higher per-unit rate at lower operating costs, so they make out fine. And any surplus gets rolled back into the effort: some as tax credits or rebates for helping the gluttons reduce their consumption (and their bills), some toward more installed capacity of the clean, sustainable, distributed kind.

    I agree, we will probably be using fossil fuels for some time. But the problem with the present system is its stress on raw capacity rather than slashing consumption, and only dirty, bulky fuels can supply that model. A normal power plant burns three trainloads of coal every single day. (One and a half of those trainloads vanishes in transmission.) The best part about conservation-based models is that they buy us time; drug addicts make bad choices because they need their stuff NOW, and certain pushers of the product aren't above using that hunger to steer behaviors.

    If we reduce demand and yes, raise electricity prices according to behavior, we can win space to make good, strategic decisions about our energy futures -- not stopgaps tossed together under the pressure of rolling blackouts. The utilities will get their profits, since they are selling caviar rather than potatoes. Renewables suddenly become a major player in our energy matrix. And consumers -- those that buy in -- will see that even at increased kWh rates they are saving money on their utility bills. It's like a little stimulus check every month, money that had been going down the proverbial rathole. Pay down debt, save for the future, buy health insurance, put another solar panel on the roof ... all things that need doing.
  • System2System2 Posts: 6,290 admin
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    Utilities would be allowed to pocket some of the difference; widespread conservation means they sell less product, but they can charge a higher per-unit rate at lower operating costs, so they make out fine.



    Back in the '80's and the drought in Los Angeles, DWP (Department of Water and Power) was turned down for a rate increase just prior to the drought being declared. The residence of LA were threatened with mandatory water restrictions if they did not voluntarily conserve. The citizens did such a great job of conserving that DWP got their rate increase simply because they were no not selling enough water. Shortly there after the drought was declared ended.

    I have a problem for being charged more for something when I use less of it.

    Let me see, you dropped your mileage from 200 miles a week to 100 miles per week, ok great job so instead of paying $2 per gallon you pay $3 per gallon so I don't loose any revenue. Sorry, that is the type of thinking that keeps us from progressing.

    Bob, I really don't want to sound rude, but do you work for a utility company or what?

    Just Curious

    The 300lb Gorilla

  • AntronXAntronX Solar Expert Posts: 462 ✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that
    Re: distributed generation. It's worth noting that over half the electricity generated in the US is lost in the wires. Some estimates say 70%.

    Hello Bob. Could you provide me a source of this information? I have been looking for information about grid efficiency. One electrical utility employee told me that average loss is about 7%.
  • BB.BB. Super Moderators, Administrators Posts: 31,684 admin
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    From what I have read and seen... The TOTAL loss from fuel to power at the home is around ~66%-75%... About 50%-65% (+/- quite a bit depending on the fuel type and how modern the power station is) is "lost" while making the electricity--the balance is lost in the transmission and distribution system... 7% may be a bit on the low side for T&L losses--but certainly possible.

    Natural gas turbines can be over 50% efficient... Coal fired plants can be down around 35% efficient (from what I recall).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Bob McGovernBob McGovern Solar Expert Posts: 25
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    Sal: :D Not likely -- since I'm not even hooked up to the utility grid. I'm not saying they get to keep all the increased rates, just a tiny sliver of it. PSCs currently guarantee profit margins for utilities when they set prices; this is more of the same. But we hafta throw the utilities a bone to secure their participation, because right now the only way they can increase profit is to sell us more of their electricity, which is a stupid model.

    Can we agree that one cause of Americans' sloppy power is is artificially low electricity rates in most areas? (California may be an exception -- their very high kWh rates are probably close to proper.) I'm advocating a modest increase for modest users -- say 10 cents per kWh instead of eight. These people are already living right and would likely notice no change in their bills.

    But as households exceed the 12kWh/day level, the rate scale needs to increase sharply. Right now there's no punitive effect for wasting electrons. The difference between 12 kWh/day (frugal) and 40 kWh/day (pig) is trivial, maybe $75 a month; unless you create a steep pricing scale, where is the incentive to change out the water heater or buy an EnergyStar fridge or turn out the porch lights?

    Several municipalities have instituted graduated electricity rates based on consumption; they have seen good results. The only way to get an American's attention is to kick him repeatedly in the wallet.:D It's like the nickel deposit on cans and bottles. Sure it's a pain and seems like Nanny Stateism, but those places with bottle bills save on litter pickup and landfills, to the general benefit.

    Here are some graphic comparisons between flat unit pricing and my triple-every-12kWh scheme, starting at 10 cent per kWh:

    Flat rate:
    12 = $36/month
    20 = $60
    30 = $90
    40 = $120

    12 = $36
    20 = $180
    30 = $810
    40 = $3240/month

    Okay, it's a brutal curve. We can discuss better trigger points and graduations if you wish. But I can promise you, anybody currently using 38 kWh/day will think really hard about saving electricity. They'll really want to find ways to shed a few watts. And the punishment money should mostly be rolled into grants and credits to help them do that.

    Some problems I foresee with this scheme: we'd need a way to protect renters from landlords who don't care, and landlords from power-wasting renters. The poor and people on fixed incomes are least-equipped to upgrade their houses, and often they have older, less-efficient homes. OTOH, poor people tend to use less power than rich ones. And people right on the breaks might feel shafted, but they are also in the best position to move into the lower pricing tier.

    As for transmission losses: my various and admittedly greenish sources may have been including things like idling power plants in that number, since some sources claim losses under 20% as transmission per se. I'm guessing the very highest numbers may include generation inefficiencies, too.

    The latest National Geographic, which is pretty liberal, puts "Electrical Loss" at 89.3 percent of residential energy and says "for every kilowatt-hour used, 2.2 are 'lost' as that energy is generated and sent over transmission lines"(March 2009, p.67). Popular Mechanics, which definitely ain't liberal, listed transmission losses specifically at 50% in a recent issue dedicated to energy savings (which I can't find, darn it); but in the May 2008 issue (p.69) speaks of the "400 billion kwh now lost while current flows through long-distance transmission lines." That's only about 10%. I would bet the last mile is a killer, though, as electricity is down-stepped again and again to 440VAC.

    Upshot is it's hard to find consistent estimates for transmission losses, since everybody has an agenda and 'transmission loss' is a slippery phrase. I see numbers like 7.5%, 18%, 50%, and 70% all lumped under the heading 'transmission loss'.:confused:
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    i don't think that placing a higher rate curve will do that much in most cases. a few may be gungho ready to conserve and they'll break even with that kind of a proposal. some may do some conserving and windup paying double instead of triple. and so on, but most will do nothing with their habits even though warranted. the proof is in cars and how people address them comparatively. that change with cars really came from forcing detroit to do its job with better mileage. i propose the same can be said here for power generation. it is not our faults that we paid them for the transmission of this power (not to be confused with the generation of this power) and they put it in their pockets as nearly pure profit. i see little to no maintaining of those grid wires going on let alone upgrades as is needed. the next generator could be placed closer to the outer new loads too rather than centralized at the power station that often will need more land acquired there to do it over the same lossy wires. this is equal to someone needing 100w in pv and send it down say #10 for a 50ft run. then every year afterwards you need more power and upgrade by 50-100w in pv each year without touching the wires. it doesn't take a genius to conclude what the results are so many years down the road of doing that is. it is hypocritical to tell me or anybody else to pay more for electricity when they lose so much of it because they (the utilities) failed to maintain or upgrade said wires, that were paid for by me and many others, that in turn causes huge losses of electricity. i agree with conserving, but not all of this is the consumer's fault as the utilities aren't even maintaining or upgrading what they have been paid to do, let alone them conserving. why is it only the consumer that is made out to be the culprit and pay for it?:grr
    ps- those same utilities are the entities that have fought the implementation of renewable energy. many utilities still make that difficult when so many people are trying their best to not only conserve, but to give back to the system. off grid is a different world and i can understand that, but there's no need for consumers to pay more to utilities as that is only a reward to the utilities that is unearned imho.
  • AntronXAntronX Solar Expert Posts: 462 ✭✭
    Transmission and distribution line electrical loss and efficiency

    I tried looking for an issue of National Geographic online, but no luck. I tried searching for "electrical grid efficiency" on Google and found this article:
    According to data from the Energy Information Administration, net generation in the US came to over 3.9 billion megawatt hours (MWh) in 2005 while retail power sales during that year were about 3.6 billion MWh. T&D losses amounted to 239 million MWh, or 6.1% of net generation. Multiplying that number by the national average retail price of electricity for 2005, we can estimate those losses came at a cost to the US economy of just under $19.5 billion. (source: http://www.renewableenergyworld.com/rea/news/article/2007/07/energy-efficiency-in-the-power-grid-49238)

    So, average transmission line loss in USA in 2005 was 6.1% or efficiency of said system was 93.9%. That's not bad at all.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    i don't believe those figures. just figuring on resistive losses alone would be astronomically higher than that even with the high voltages they use. that's the problem with the grid as the resistive losses are far too high and they have admitted it is far outdated. that means they were doing what i cited in the pv example, but i should've stated adding them each year in parallel. losses can be held by upping the voltage, but then you get to replacing massive transformers all of the time too and you do hit a limit. they've hit that limit long ago.
    my question is why do i pay for its transmission if they aren't using that money to upgrade and maintain the wires with it? thicker wires and/or more of them would also ease the problems facing the grid, but utilities get off scott free while making consumers pay for it. the utilities just complain to their puc or equivalent and say they need more $ and get it. maybe those agencies like the puc should be saying no to them because they alreay have been paid funds by consumers to do that grid upgrading and maintenance and better yet threaten to revoke those funds if they continue failing to do the maintenance and upgrades needed on the grid.
  • Bob McGovernBob McGovern Solar Expert Posts: 25
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    Niel: you make excellent points. But the utilities aren't just adding capacity for the heck of it -- it's consumers who are driving demand. Utes just try to meet that demand at the lowest possible cost to themselves.

    The median US household consumes 30-35 kWh per day. That's twice what western Europe and Japan use (tho both are increasing). We are gluttons because our power has been too cheap for too long, and there has been little incentive to conserve.

    When gasoline hit $4.50 a gallon people stopped buying Hummers and, to the extent our suburbanized lives allow, cut back their driving. Because it hurt, bad, to fill up that tank. Mandating higher CAFE standards is one important tool, but will it matter if everyone drives individual cars 15,000 miles a year at 70 mph? I feel our individual and collective behaviors are the root of the matter and, usefully, within our power to change. If we got median consumption down to 12 kWh per day, an astounding number of good options would open up. At 30 kWh per day, we have only bad options and RE will never be more than a bit player.

    ETA: Look at that state-by-state list of energy use linked above. Notice how sweetly consumption is the inverse of average kWh price. California, with some of the highest rates, has almost the lowest household consumption. Ditto New England. Idaho, at 6.37 cents per kWh, uses almost twice as much power per residence.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Potential of Solar to Replace Fossil etc. Capacity Needed to do that

    i acknowledged that conservation is needed. it was i who came up with and suggested to naws the category of energy use and conservation in this forum. yes, we are spoiled to a large degree, but so are the utilities as they do little to nothing even when paid to do it. you also forget the population is also increasing fast too so it is more people using the power and not the same number of people just using more every year. you are failing to acknowledge that it isn't just the consumer who is at fault and you would like to reward the utilities to punish the consumers.
    as to the gasoline example you gave yes, i can say to a point that is true and i said that in so many words before. it isn't as you say they stopped buying as they didn't all stop buying. another factor is the economy and the number of people now unemployed too. i'll bet even hybrid sales went down and you can't blame higher gas costs for that. then again many whose standard of living was lowered some, but managed to keep working may have been scared towards the other cars, but not just because of gas prices so hybrids may be steady.
    the bottom line here is, why should i or anybody else be expected to pay an unearned penalty to the utilities when they have a worse track record than the consumers do? they are more guilty in their bad attitudes and waste far more than we do.
    also note that many of the states with better renewable energy programs will offset the actual consumption greatly and that isn't shown or readjusted for in that link.
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