About the SA Blog Network

Guest Blog

Guest Blog

Commentary invited by editors of Scientific American
Guest Blog HomeAboutContact

The Backbone of the Electric System: A Legacy of Coal and the Challenge of Renewables

The views expressed are those of the author and are not necessarily those of Scientific American.

Email   PrintPrint

“Energy policy” and “clean energy” may be political hot buttons this year, but the technological realities and challenges to achieving energy and environmental goals are seldom discussed. There is strong public sentiment that the U.S. should decrease our reliance on fossil fuels because of concerns about pollution, global warming, ecosystem damage, and energy security. Although a domestically abundant energy source, coal power is imputed as being a major contributor to smog, acid rain, and global warming. High-profile accidents associated with coal mining and coal ash management have further damaged coal’s reputation. Grass-roots campaigns to replace coal as a major source of electricity claim that wind, solar, and geothermal power could replace retired coal capacity.

In 2011, 42% of the electricity generated in the U.S. was from coal, according to the Energy Information Administration. Although coal generation for 2012 is projected to fall 15 percent, coal is still expected to represent a significant percent of the nation’s generating capacity through 2035. Reducing reliance on coal faces challenges beyond policy and market economics. What are the technical constraints of the U.S. electric generating system, what role does coal power play, and how can we further incorporate renewable energy sources?

Figure 1. The U.S. Electric Grid

Figure 1. The U.S. Electric Grid

To understand the technological challenges, it is helpful to understand the roots of U.S. electrification – how our electrical system evolved, and the legacy of coal power within that system. Modern coal-fired power generation is a vestige of Thomas Edison’s 1882 Pearl Street Station, which was the first coal power station to provide electricity to residents of New York City. With the introduction of alternating current (AC) by Westinghouse Electric, by the early 1900s power could be successfully transmitted over long distances, allowing centralized stations to deliver power to population centers connected by high voltage transmission lines. Although turn-of-the-century electric power came from numerous smaller generators, improvements to steam power turbine technology coupled with economies-of-scale further encouraged the consolidation of electric power.

Transmission technology improved as well during the early part of the 20th century. Increased voltage capacity enabled power to be more efficiently carried for longer distances. Utility companies were able to interconnect multiple plants, allowing the most efficient plants to deliver power to a wide area, provide backup power, and further reduce electricity costs. The use of coal for electric generation expanded rapidly to support soaring electricity demand during World War II, and the transmission grid was built to take advantage of centralized power generation. The legacy of that growth and consolidation is that large coal power plants still dominate the U.S. electric system, and the infrastructure for carrying high-voltage power (see Figure 1) from smaller, distributed sources is lacking.

Figure 2.Summer Generating Capacity by Energy Source

Figure 2.Summer Generating Capacity by Energy Source

The electric system necessitates a real-time balancing of demand with generation. Appliances, air conditioning, and the power to feed our increasingly wireless lives require electric generation be delivered to meet that demand. Failing to meet electric demand results in blackouts with severe economic consequences – think Northeast Blackout of 2003.

The electric generated by all sources – coal, nuclear, wind, solar, geothermal, biomass, natural gas, etc. – must be delivered by the wires, buses, transformers, substations, and ancillary equipment that comprise the transmission grid. These components have physical constraints, including thermal limits (related to sag of the transmission wire) and voltage stability (related to the ability to prevent sudden voltage dips that can lead to failures). Sometimes a specific power plant is needed to maintain electric reliability, as was the case for five of First Energy’s coal plants that were scheduled to retire but are required to continue operating for voltage support. The electric system relies on redundancies including operating reserve (excess capacity) to ensure reliability.

Baseload generation currently provides the backbone for the electric grid. Baseload is the minimum level of electric demand over 24 hours, such as during late evening or early morning and is served by plants that provide steady and low-cost power with few unscheduled outages. Nuclear and coal have predominately served as baseload plants because they operate most efficiently at full, steady output and are slow to ramp up or down. Geothermal and hydropower have also been used in certain areas as baseload power. Hydropower with pumped storage is a flexible energy source able to serve sudden spikes in demand, such as during hot summer days (peak demand). Natural gas turbines, which can quickly ramp up or down to follow electric load, have been a preferred source of peaking power.

Load-following or intermediate demand plants provide power in between off-peak and peak hours, which is when solar and wind power have had the most use. Intermittent or diurnal sources such as wind and solar have been widely considered unsuitable for baseload generation because of their variability. In other words, you can’t count on them to meet demand 24×7. Energy storage may help bridge the gap for intermittent generating sources. Success with baseload solar power is promising, while other energy storage technologies are still under development.

So why can’t we just use wind and solar when available, supplement with current energy storage capabilities, and use quick-start resources such as natural gas turbines as needed? The problem lies with transmission constraints. While some studies have shown that load shifting using energy storage could help eliminate minimum generation constraints, these technologies have not reached wide-scale deployment and transmission infrastructure is lacking to fully support distributed renewable generation.

Regional differences in available electric generating sources compound the problem. While some states such as California generate only a small percentage of power from coal, in other states including Kentucky and Indiana, over 85 percent of electricity generation is from coal. Hydropower sites are abundant in the Pacific Northwest, but relatively few installations exist in some areas of the U.S.. As a result, regional transmission system operators responsible for balancing load and maintaining electric reliability face a range of technical challenges. What works in the Northeast will not work in Texas. Each system has to find a way to incorporate renewable sources given the existing generating fleet, existing transmission infrastructure, and planned improvements.

So we have an electric system based on large, centralized baseload plants that run (nearly) continuously and power that must be delivered in real-time by a transmission grid that needs modernization. To increase the complexity of this high-wire balancing act, increasing numbers of plug-in electric vehicles (EVs) are projected to hit the roadways. While electrification of transportation will help decrease reliance on fossil fuels, where will the power for those EVs come from? In some areas of the country, the answer right now is coal.

Retiring older coal plants that operate off-peak can occur without impacting electric reliability, and is evidenced by the slate of recent retirement announcements. But replacing baseload coal generation with alternative power sources will be more difficult. Some people see repowering with natural gas as the solution, as carbon emissions from natural gas generation are 45 percent less than coal per megawatt-hour. Natural gas generation could serve as baseload generation, but opposition to hydraulic fracturing spurs concerns about future supply and potential price spikes. Permitting and constructing new nuclear plants is fraught with difficulties, partly due to opposition from environmental groups and ensuing cost overruns.

Some envision smart grid technologies and transmission upgrades completely eliminating the reliance on baseload “must-run” generation, with an electric system powered mostly by renewable sources. Because renewable sources tend to be much smaller than coal-fired power plants, and located in areas that may not have sufficient transmission access, simply replacing coal for renewables is not straightforward. To reach 80 percent “clean energy” – including combined cycle natural gas generation as clean – would require the replacement of 35 percent of summer generating capacity (see Figure 2, coal + petroleum). The technological scale of such build out (over 370 gigawatts) is astounding. That would require about 185,000 2-megawatt wind turbines or over 700 large (500-megawatt) solar farms. Considering that even solar and wind projects have faced local opposition, this is a tall order.

Of course, the solution does not have to be an either-or situation. Perhaps the “all-of-the-above” approach must necessarily include coal power in the near future. Newer coal plants have advanced pollution controls and far lower emissions than older coal plants, and provide the bridge between the legacy transmission system and the electric grid of the future. What is clear is that an “all-of-the-above” energy policy must first consider transmission planning and improvements, demand-side management, and energy storage as the first steps in reinventing our electric system.

Dawn Santoianni About the Author: Dawn Santoianni is a combustion engineer who has worked on energy and environmental issues for 20 years. She has conducted air pollution research as a contractor for the U.S. Environmental Protection Agency and testified before a Congressional subcommittee on a proposed environmental regulation. She currently works as technical writing consultant through her company, Tau Technical Communications LLC. When she is not debating or blogging about energy policy, Dawn spends time at her “cool” job – volunteering at an educational wildlife facility where she helps care for lions, tigers and wolves. She enjoys reading about particle physics and is intrigued by the experiments at the Large Hadron Collider. Follow on Twitter @tautechnical.

The views expressed are those of the author and are not necessarily those of Scientific American.

Comments 28 Comments

Add Comment
  1. 1. GilbertEA 5:12 pm 05/17/2012

    The War on Coal continues to draw on and on but is is becoming apparent that the transition from the backbone of energy in America is going to be a rough road ahead. The issue lies in the fact that as we try to be progressive, we often don’t have necessary replacements for the things we’re taking away.What was once a business transition is now an annexation because of the compliance costs or being shut down all together ( As the author Dawn says above, it doesn’t need to be an either/ or decision BUT, we do need to develop some sort of an understanding between regulatory policy regarding coal facilities and the businesses that rely on it.

    Link to this
  2. 2. JamesDavis 5:17 pm 05/17/2012

    I do not see where you are going with this. Replace an old coal burning power plant with either a hydro or geothermal (which is hot all over the U.S., and there is plenty of water.) and get a never ending power source, or, replace oil, coal, and natural gas power plant with a new mini thorium power plant and still have a never ending power source. If the grid can handle the coal, oil, and natural gas energy sources, then it can handle the nuclear, solar, hydro, wind, and wave source of power generation. It sounds like there are a lot of greedy people trying to find excuses to stay away from clean energy. Get off your asses and get those geothermal power plants and thorium power plants built and let’s stop this worthless debate on what we cannot do and what we can do.

    Link to this
  3. 3. DawnSantoianni 6:04 pm 05/17/2012

    James, the problem is that you can’t always replace a fossil fuel plant with hydro or geo at exactly the same location. There are limited undeveloped hydro sites remaining, although run-of-river (smaller hydro) could be an option. So if you can’t put in a renewable source at exactly the same location as the fossil power source, then the ability to incorporate that RE depends on the existing transmission infrastructure, access rights, and fees. The intermittent nature of some renewables means you still need backup power that is ready to go, but with emerging storage technologies we can bridge that gap. I agree with you that geothermal and mini-nuclear are great options. The point is that you can’t shut down every coal plant tomorrow and expect to maintain electric reliability. That is why regional transmission authorities say they still need coal units that have been slated to retire to maintain reliability.

    Link to this
  4. 4. DawnSantoianni 6:11 pm 05/17/2012

    Gilbert, I think what we need is an environmental regulatory policy that is coordinated and planned with an energy policy, with achievable timelines. As a country we’ve been in reactive mode, which does not yield the most economical, business-friendly (fossil and RE companies alike), or environmentally-protective result.

    Link to this
  5. 5. sethdayal 7:09 pm 05/17/2012

    “…carbon emissions from natural gas generation are 45 percent less than coal per megawatt-hour.”

    This is a gross error. There are numerous studies which show gas with all its methane leaks from production to delivery produces just as many GHG’s as coal, and fracked gas even more.

    “..Permitting and constructing new nuclear plants is fraught with difficulties, partly due to opposition from environmental groups and ensuing cost overruns.”

    The AP-1000 nukes currently under construction in the US have twins already 90% complete in China on time and on budget at half the cost. The only conceivable cost overruns in the US will be from corrupt and incompetent US contractors and an out of control regulator – shouldn’t happen.

    With a fossil to nuke conversion no transmission builds are needed as each 100K of population has its own nuke.

    The current cost of the first of kind AP-1000 is 4 cents kwh when built by efficient public power operators like TVA and Bonneville. That cost would drop to less than 3 cents a kwh with factory production and less than a cent if the corrupt politicians in the White house put a tiny fraction of the money into the molten salt reactor as they are boosting Big Oil’s carbon capture scam.

    No matter the Chinese will be selling us back our MSR’s within the next 5 years.

    The biggest problem facing nukes are corrupt politicians and utility exec’s all purchased by Big Oil money who push the cheap natural gas canard. The cost to deliver today’s gas is $9/mcf and the selling price of $2/mcf is only a $2/mcf tanker ride away from a $18/mcf market.

    Renewables are an order of magnitude more costly when gas backup and 5 times sized transmission builds are included and two orders when a buck a kwh storage replaces gas backup. The current renewable/gas backup scam using inefficient gas backup run inefficiently produces more GHG’s than it saves. Less GHG’s much less money replacing the renewables with efficient CCGT plant or nukes.

    Link to this
  6. 6. sethdayal 7:20 pm 05/17/2012

    Note as well that the AP-1000 nuke is designed to load following cycling from 100% to 50% back to 100% easily.

    Link to this
  7. 7. alan6302 9:23 pm 05/17/2012

    What effect will the dec superflare have on the grid.

    Link to this
  8. 8. Carlyle 12:28 am 05/18/2012

    Thank you Dawn. A balanced summary of the infrastructure problems. Hydro can not be fully relied upon, let alone the other renewables. If the western world wishes to remain economically relevant in manufacturing, we must cease pandering to interests that block the development of new nuclear facilities in favour of non solutions that will not only not cater for our energy needes but in fact contribute to more polution & waste of resources. Whether it be bio fuel, wind, solar or hydro, they all have their downsides environmentally. Nuclear, despite its problems, is the best solution.

    Link to this
  9. 9. DawnSantoianni 6:52 am 05/18/2012

    Seth – point taken about carbon emissions from natural gas production to delivery. While the CO2 emissions are 45 percent of coal, there have been studies that have suggested methane emissions make natural gas less attractive. I refer readers to another piece from SA that appeared earlier this year:

    I don’t think it is accurate to compare public opposition in US with China. At an expert forum I recently attended, regulatory agency representatives commented on the permitting process in US vs. China, particularly NIMBYism. I don’t agree that the problem is corrupt politicians and utility execs. That may make a sound bite, but in reality “we the people” are all the problem. Our power demands and our reluctance to recognize that all energy solutions and moving forward toward a more sustainable energy future will depend on compromises.

    Link to this
  10. 10. JamesDavis 7:03 am 05/18/2012

    “Carlyle”, I agree with you and “sethdayal”. Nuclear is one of the answers but not necessarily the best answer unless you go with the nuclear power plants that can be mass produced on an assembly line like the mini nuke can and transported to its location. These nuke plants, designed and built by Westinghouse, are very proficient and cheap to build, and can be placed in every city and suburb. You will only need to use these nukes where geothermal or ocean wave energy is not available. Solar, placed on homes, can produce an incredible backup system. There are 14 geothermal power plants in operation in the U.S. and if they were utilized properly, they could provide an incredible income for the country and the people where the the power plant is located could get free electricity. The brine from geothermal power plants contain rare minerals like gold, silver, and lithium. We are talking 15 tons a year of silver, about three tons of gold, and 100 tones of lithium, and there are many more. The only thing a nuclear power plant gives you is electricity and then you have to deal with the waste. A geothermal gives you electricity and there is only 1% pollution and they give you these rare minerals. So ocean and river wave, solar, wind, and geothermal should be your first choice for clean energy, and molten salt as your back-up storage battery.

    Link to this
  11. 11. DawnSantoianni 7:06 am 05/18/2012

    Carlyle – thanks for the comment. I agree nuclear must be a part of the solution.

    Link to this
  12. 12. doctordawg 7:09 am 05/18/2012

    I don’t get this. This sounds like a shill for so-called “clean” gas and larger grids vs. clean solar and wind at the point of consumption.

    I have a 3.4Kwh solar grid on my house. It takes up about one quarter of my entire modest home’s roof. It can’t be seen from the road, so it’s really nothing.

    It generates MORE than I can use. My A/C sucks up about 1.2Kw on a hot afternoon. I can run it along with my 450w refrigerator and washing machine at noon and my meter still runs backwards, while the panels provide shade on the sunniest surfaces, keeping things even cooler.

    I changed my lighting to all LEDs, including replacing some 80w fluorescent tubes with 18w LED strips. It looks the same, so my overnight usage, including the 90w dual core laptop I’m writing this with, has dropped to less than one old-school three-way light bulb.

    Why is this so hard? Because it’s hard to monetize on Wall Street. It’s a no-brainer investment for me. After tax credits and rebates, I am averaging a 9% return on my money invested, and will have paid the system off completely in less than six years – this with a 25 year warranty on the panels – so I’m looking at 19 net positive years of guaranteed outstanding returns with no broker skimming off fees.

    When, not if, electric rates skyrocket – who cares? All it means to me is my investment pays off faster and I make an even better rate of return.

    This isn’t theoretical. It’s not anecdotal. It’s working for me now. Without burning “clean gas.”

    Link to this
  13. 13. DawnSantoianni 7:11 am 05/18/2012

    A few people have emailed asking for a better version of Figure 1, the US electric grid. While I have a link to the fully interactive map within in the text, some people have missed it. Figure 1 is a screenshot courtesy of the NPR interactive map where you can compare transmission infrastructure with power plant locations, and hydro, wind, and solar potential locations. It can be found at:

    Link to this
  14. 14. doctordawg 7:27 am 05/18/2012

    Thanks for the bigger map. It shows huge proposed multi-state solar power transmission lines. My solar power transmission line runs less than two feet from my Sunny Boy inverter to my breaker box.

    Again, why is this not a better option for millions of sunny state Americans than this giant infrastructure rollout? Sure, some live deep in the woods where solar isn’t an option, but I look out over the San Fernando Valley while needlessly dusting my photon farm and see NO other solar installation as far as the eye can see. None. Zip.

    My net meter has been negative since the day I turned it on. Why the deafening silence?

    Link to this
  15. 15. DawnSantoianni 8:13 am 05/18/2012

    doctordawg – in areas of the country where solar energy is intense enough, community-based and individual installations including rooftop solar would really move us toward a sustainable solution. Of course in other areas of the country, solar wouldn’t be a good option, and that is why looking at energy production on regional basis is so important. Moving from an electric grid that is based on centralized plants to a distributed electric system will need transmission build out, and yes more people implementing home-, business-, and community-based power generation.

    One point I will make about individual implementation such as rooftop solar panels is that even though there are incentives and tax breaks, the upfront cost automatically prices out lower-income families. Community-based solutions could help reach homes that normally wouldn’t be able to afford the technology.

    Link to this
  16. 16. Carlyle 9:03 am 05/18/2012

    12. doctordawg 7:09 am 05/18/2012
    Your solar panels are subsidized by other consumers who can not afford such a system & by the backup power grid that you use at night time or in bad weather. What is more the back up system has to be generating power to cover your needs in case a cloud should pass over. Unless you disconnect from the grid, you get the warm & fuzzy feeling at others expense & save practically nothing so far as CO2 generation is concerned. In fact you well may increase it. Solar hot water being practically the only good exception in most cases.

    Link to this
  17. 17. dwbd 12:21 pm 05/18/2012

    Wind Energy is just:

    a) greenwashing for Natural Gas,

    b) a sleazy trick to force Nuclear & Coal out of the Electricity Market and replace them with Natural Gas, since it is not economical to build big expensive modern Coal & Nuclear plants and have to shut them down for large periods or run them at substantially reduced capacity because Wind happens to be high at the time. Wind essentially destroys Baseload Power and turns it into a new form of Peak Demand power – a role that NG generation has always provided.

    c) a way to push up Electricity prices so they won’t look so bad when NG costs skyrocket to International levels about 5X what domestic prices are and also make Electricity too expensive to be attractive as an Energy Substitute for Oil & NG when those commodities are horrendously expensive. Energy Substitution – Electricity for Oil or Gas – is a nightmare Big Oil will use any and all devious means to avoid.

    Texas to install world’s largest wind energy storage system:

    “…That’s one big battery. Such technology is likely to become crucial as wind farms become ever larger but erratic suppliers of electricity to the grid…”

    So now we say the despicable game being played on the public. First we pay 2-3X going power rates for short lived Wind Turbines, that produce mostly a useless form of energy, and now realizing how worthless wind energy is its:

    “…we didn’t know, the wind doesn’t integrate well into the grid, how terrible a discovery. Go figure. So now we have to add $billions in energy storage…”

    This will convert the worthless wind energy into something useful, easily tripling the cost of the already high priced wind. and guess who gets to pay for that. Yep, John Q. Public – not the Wind Farms or the Wall St. Financial Meltdown Specialists who are profiting from the lucrative subsidies and huge tax incentives given to Big Money Wind Farm investors.

    This is the scenario being played out right now in Ontario with only 1.9GW of the planned 10GW of Wind installed. Hydro is routinely spilled and Nuclear Dumped, with ZERO emissions or cost savings, in order to accept Wind during nightime, weekends, spring/fall when Wind is high and Grid demand is low. Often Ohio & Quebec must be paid as much as 14 cents per kwh to accept the Wind nobody wants, while Ontarians must buy the Wind power for 13.5 cents per kwh. A criminal assault on the integrity of the grid and on downtrodden poor & middle class who can’t afford this outrage.

    Link to this
  18. 18. mstraub 12:51 pm 05/18/2012

    Coal needs to no help from politicians, the world is dependent on the old, dirty stuff and will be hooked for a long, long time. But if the only argument to keep it alive is because nothing else is baseload, well then you’re just not looking hard enough. Baseload renewable power is here in many clean forms, just take a look to the oceans. I’m talking about Ocean Thermal Energy Conversion (OTEC), no drilling under the sea required, just a 24/7/365 flow of clean power created from the temperature difference in shallow and deep water. Plus, the only byproduct of an OTEC system is millions of gallons of clean drinking water.

    These are the kinds of ideas that will improve the lives of millions for generations to come, and they’re happening today. See how OTEC works and the people making it happen at The On Project.

    Link to this
  19. 19. SigmaEyes 3:24 pm 05/18/2012

    This is such a nicely balanced article. Only those with extreme prejudices for or against one form of energy production would argue (see nuclear comments).

    I think a main point of yours is that the transition will be a process, not an event; for both transmission and generation of power.

    My own preference is for a system dominated by decentralized generation at or near the source to reduce the demands on the grid and to lower the upgrade costs of our grid. Seventy percent of the population lives near the coast where wind, water (wave/tidal/thermal), sun, & geothermal are all viable, and transmission requirements would be relatively small. Hydro storage can be weaved into existing drinking water reservoirs to keep them full (combining the storing of potential energy and fresh water supplies).

    I believe that if electric vehicles (EV’s) become popular, there will be more demand for decentralized electrical production at our homes and small businesses.

    Just as “trickle down economics” was a con that obscured “consumer” driven capitalism and job creation, consumer demand will be the real engine that transforms energy production to decentralized renewables, in my opinion. The public is sold on the benefits; the initial price has been the obstacle in the mainstream.

    Now with China dumping imported PV panels, and existing public subsidies, all that is required is the need to fuel your EV at home to open the flood gates of demand.

    That should lighten the load on the transmission grid, (although energy usage is climbing at about 5% per year) – giving time for the process of upgrading and evolving the existing grid.

    In the world that exists in my little mind, it all works out perfectly!

    Link to this
  20. 20. Carlyle 6:51 pm 05/18/2012

    RE: 18. mstraub 12:51 pm 05/18/2012 Ocean Thermal Energy Conversion
    Before you get too excited about that concept you need to learn about the Carnot Cycle. With no losses through things like friction or the water being warmed as it rises from the depths etc (impossible) a 10 degree C temperature difference gives you a theoretically possible 3.5 percent efficiency. The scale needed for worthwhile energy recovery makes it another money burn. If you want to enter different temperatures into the tool below, it works in Kelvins. The two reference temperatures for Celsius, the freezing point of water (0°C), and the boiling point of water (100°C), correspond to 273.15K and 373.15K, respectively.

    Read more: Kelvin temperature scale —
    Have fun. It is interesting & I am not having a go at you. Education is the problem. That is why shysters are able to milk millions in grants.
    19. SigmaEyes
    3:24 pm 05/18/2012 Your prefered schemes suffer from similar problems that the promoters do not mention.

    Link to this
  21. 21. GreenMind 8:05 pm 05/18/2012

    Nice article, Alysin, but incomplete. There are options that you are missing. One is conservation. That is by far the best return on investment of all options. The very poor tend to rent rather than own, and landlords can be induced to insulate rental properties better and install more efficient facilities in exchange for a cut of the savings in power. Homes can be insulated so well that no air conditioning is needed at all, even during hot summer days in the 90s. In know because the house I live in is insulated that well.

    Another option is the pilot project that Venice, Italy, has started building. It uses algae to collect the sun’s energy while using the CO2 from an electric plant to feed the algae. The algae is harvested and fed right into the electric plant combustion chamber without the need for extensive drying. It can be used for fuel at any time of day or night, and so provides its own form of solar energy storage. In this system the CO2, the nutrients and the water are all recirculated in a closed system. If the algae ever falls behind, additional CO2 could be added easily simply by burning additional fossil fuel.
    See link:

    Finally I have to agree with doctordawg. Installing solar panels on residential rooftops can reduce demand, but then allowing the owners to sell ALL excess power back to the utility would result in a big boom of installation. Currently most power companies are not required to buy that power back, and so homeowners only install as much capacity as they can use themselves. But if power companies had to buy all of the excess then homeowners could install much more, and that would help leverage the cost of the installation and the inverter. Sure, you still may have to be connected to the net, but only if you don’t have enough storage to keep you through the night. But night-time energy use can be reduced a lot with better lighting efficiency, better refrigerator efficiency, and by doing heavy tasks like washing and drying during the day. A few ordinary heavy-duty car batteries can go a long way. And one projected use for electric cars is to provide power for the house during the night.

    Dawn Santoianni, you say: “One point I will make about individual implementation such as rooftop solar panels is that even though there are incentives and tax breaks, the upfront cost automatically prices out lower-income families. Community-based solutions could help reach homes that normally wouldn’t be able to afford the technology.”
    There are now companies that pay for the entire installation costs, and then charge the owners or renters a monthly fee, which is often less than they would have paid for electricity. The company retains ownership of the installation, which simplifies the maintenance, upgrading, and the process of selling a home with the installation added.

    Finally, some entire school districts have installed solar arrays over their parking lots at every school, which has the unintended benefit of providing shade for the cars parked under them, and for students looking for a shaded place when it is very hot out. There are enormous parking lots surrounding enormous malls and big box stores, and they could save big on energy costs by doing the same.

    Link to this
  22. 22. dwbd 11:21 pm 05/18/2012

    A lot of commenters have no clue as to the urgency of the Energy problem. The per capita Power consumption in the USA is 11,300 watts or 396 MWh of total thermal energy for a family of four share. So if we are using the CHEAPEST of new Renewables at 10 cents per kwh that’s $40,000 per yr per family of four just for Energy. Add grid costs, storage, backup generation, transmission and you will easily double that to $80,000 per yr. Do you seriously think that is viable? It ain’t.

    Let me make this perfectly clear. We continue with rapidly depleting Oil, Gas & Coal or we switch to Nuclear Energy. There is NO OTHER CHOICE. That is just the facts.

    For those Pixie power dreamers, who don’t want to actually work the numbers, here is a good start for an education on the harsh reality of Energy production:

    doctordawg’s Solar power is heavily subsidized by the taxpayer – for what? So food can be taken out of the mouth’s of children so he can claim “I’m green”. A good analysis of doctordawg’s Solar Subsidies here:

    Latest NREL data on sunny California shows average cost of Solar PV installations are $7.74 per watt peak. At 17% CF for Los Angeles, that is $45.52 per kwavg output. You can buy the latest – most highest tech machine ever built – the Virginia Class Nuclear submarine – for $2B with a 50 MW nuclear reactor with 33 yrs refuel cycle. 5 yr build time – start to finish. That’s $40k per kwavg, with lots of added features you don’t need, like missiles, sonar, living quarters for 134 etc. And gives you power for 33 yrs, even when the sun isn’t shining.

    EIA puts 2011 Solar PV @ 21.1 cents per kwh levelized cost for delivery in 2016 and Solar Thermal @ 31.2 cents per kwh vs Nuclear @ 11.4 cents & Gas @ 6.6 to 12.5 cents, Coal @9.5 to 13.6 cents/kwh.

    The Solar & Wind are curiously missing a variable O&M cost – which most certainly should be added – they do have maintenance costs – and down time.

    And Solar & Wind require major Grid Integration costs – overbuild – storage – shadowing generation can easily double those prices.

    doctordawg figures he’s entitled to use the Grid as a giant storage battery for free, with not even paying for Grid costs. So in the morning when his Solar is Zip, a high priced, fuel guzzling NG generator will have to start up to supply rising demand, then Solar picks up, peaks at noon, and is Zip again by 5pm and same NG fuel guzzlers must start up to replace the missing Solar power, while grid demand peaks, and continues high until late evening. doctordawg doesn’t pay for all of that, including transmission lines, peaking NG/Propane/LNG infrastructure

    Link to this
  23. 23. Carlyle 12:42 am 05/19/2012

    Re: 22. dwbd 11:21 pm 05/18/2012
    Spot on but when these realities finally hit home, who do you think will be blamed? It will not be the AGW Green disciples.

    Link to this
  24. 24. DawnSantoianni 10:23 am 05/19/2012

    SigmaEyes – thanks for the comment. Many energy experts believe that decentralizing generation is key. Distributed small-scale generation could be implemented to reduce the carbon and particulate emissions from diesel and kerosene, which are widely used in developing countries. With EVs, utility companies are working on pricing programs to encourage charging at night, when demand is lowest. Right now, however, that energy drawn would come from baseload power plants (especially night charging). The reason that utilities want to encourage off-peak charging is because of concerns about load during peak times (i.e. reduce the demand spikes).

    dwbd – while I believe that nuclear must be part of the equation for future energy production, if we put all our eggs in the nuclear basket as a strategy, we are going to run into problems. I just don’t think the public will accepting have that wide distribution and reliance on nuclear power. From a utility perspective, diversification of the generating fleet is best from an economic and risk perspective.

    GreenMind – I would have to look up the monthly fees for the companies that install solar panels free of cost, but I find it unlikely the fees would be less than a monthly electric bill. If you have studies/data otherwise, please share. Communication and public awareness is an essential component to getting wider consumer buy-in of efficiency, conservation, and energy improvements.

    One thing that people should realize is that generation is dispatched based on merit order (i.e. production cost). Those most efficient, least cost sources (regardless of type) are the first to be dispatched. Less efficient plants and more expensive sources are dispatched based on delivered electricity price.

    Link to this
  25. 25. dwbd 12:19 pm 05/19/2012

    Dawn, it isn’t a case of putting all our eggs in the Nuclear basket, instead it is a case of recognizing THE FACT that ONLY Nuclear can seriously replace fossil fuels, fossil fuels which supply 86% of the World’s Energy. Yep, conventional Hydro is good but geographical limitations mean it will remain a minor component. Same applies to Geothermal. Solar is still WAY too expensive to be a viable replacement for fossil fuels. And Wind creates more problems than it solves – it is just not a viable Energy Solution.

    So what’s left – Nuclear Power & Fossil Fuels. And I should remind people that Nuclear Power is a CLASS of Energy, just as Fossil Fuels & Renewable Energy are a Class of Energy. So “all our eggs in the Nuclear Basket” – all our eggs are already in the Fossil Fuel Basket.

    The Nuclear Basket includes:

    Fission: LWR, PHWR, BWR, CANDU, GCR, HTR, PBMR, IFR, TWR, DMSR, LFTR, SMR, RBMK, FBR, BREST, SVBR, MBIR, FNPP(Barge Reactors), Submersible Reactors, ADS(accelerator driven)

    Fusion: IEC, Focus Fusion, ICF, Reversed Field Pinch, Colliding Beam, Magnetic-Inertial-Fusion, Muon-Catalyzed Fusion

    Fission-Fusion Hybrids, LENR, Anti-matter catalyzed

    To name a few. So the Nuclear Class of Energy is a MUCH larger class than either the Fossil Fuel or the Renewable class of Energy. And ONLY Nuclear is viable EVERYWHERE – under the Sea, deep within the Earth, isolated sites like Antarctica, in Earth orbit, on the Moon or Mars, on Asteroid mines. We haven’t even begun to exploit the Nuclear capability – and the reason for that is quite simply – opposition from powerful Big Carbon vested interests. They know very well that Nuclear is the only threat to their Energy Hegemony, and they will use any & all means to block its development.

    So a total focus on replacing Fossil Fuels with Nuclear Energy is a RATIONAL Energy plan – and that doesn’t mean all our eggs in one basket – since the Fossil Fuel one basket we have now will remain for a long time to come. It means the gradual substitution of Fossil fuels with Nuclear Energy. The only feasible solution available – and almost certainly – the only solution ever available.

    Link to this
  26. 26. dwbd 12:45 pm 05/19/2012

    Dawn:”..One thing that people should realize is that generation is dispatched based on merit order (i.e. production cost)..”

    You should have added that is not generally true for the new Renewables, mostly Wind, some Solar. They are given pride-of-place on the Grid, and usually must be accepted even if totally worthless. In addition Renewable Portfolio Standards force Utilities to accept Wind & Solar that they don’t want.

    And great map of the USA grid at the NPR site, but one gripe I have is the Solar Map hypes the Electricity output available. Looking at PVwatts data their 260 kwh/yr/sq.ft. is more like 154 AC output kwh/yr/sq.ft for crystalline silicon Solar Panels. That’s more like the power to run one small LED light bulb for a year (if you use a battery to store the power).

    Link to this
  27. 27. AlexanderGreenLiving 1:23 am 10/3/2012

    Hi Dawn,
    Thank you for this, well, pretty thought out and well researched post. Honestly, I consider myself a pretty well researched green living person. Yet the amount of detail you provided on the electrical grid was very educational. I am going to have to do more research and do my own blog article, citing you of course!

    Thank you,
    Alexander Milan

    Link to this
  28. 28. BogdanT 3:35 am 01/31/2014

    Very interesting indeed. Very interesting indeed. What about a Pareto based approach?… like in this paper:

    Link to this

Add a Comment
You must sign in or register as a member to submit a comment.

More from Scientific American

Email this Article