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Saving Energy Without Derision

George Maschke writes "Saving Energy Without Derision (5 mb PDF) is a new (and free) e-book by former Sandia National Laboratories senior scientist Dr. Alan P. Zelicoff. This book is intended to be a real-world, no-nonsense, thoroughly documented collection of easy-to-implement recommendations to help the average thoughtful person to pick the 'low-hanging fruit' of conservation and renewable energy. The author is after the easy 75% of actions we can all take (but almost uniformly ignore) that most certainly make a difference in energy costs (after all that's what most people care about) and adjuring a bit of unnecessary adverse impact on the environment (which a few folks actually think is important beyond the mere dollar valuation). The author welcomes comments and intends to continuously update the book (consistent with readership interest) and address many new topics. For example, next on his list is an analysis of the economics and scientific basis of fuel-cell vehicles powered by hydrogen. (Bottom line, he maintains, is that it's a cruel hoax and energy disaster, and far less useful than, for example, heavy hybrid automobiles that get about 50 - 60 miles on an electric charge alone -- which accounts for more than 85% of driving in the US and elsewhere on a daily basis -- and which are available now.)"

11 of 698 comments (clear)

  1. Good to see! by mprinkey · · Score: 4, Interesting

    There is a definite need for energy conservation ideas that can be directly supported with economic validation. So many "green" initiatives are driven solely by politics and have economics, and often even environmental impacts, that are questionable. We need more people installing compact flourescent lamps and water heater blankets...not $20,000 solar panel arrays. A healthy dose of common sense here could really make energy efficiency ideas more popular. Here's hoping it works.

  2. The fundamental issue with Hydrogen... by Ricdude · · Score: 5, Interesting

    ...is that it isn't an energy *source*. You have to make hydrogen, either by splitting it out of water, or some hydrocarbon source (e.g. petroleum), then pressurize it to extremes in order to get any usable range out of it in an automobile. If hydrogen can be manufactured by renewable means (geothermal, for example, would work well in Iceland), then there is some benefit to it.

    However, if you use solar energy to create electricity to electrolyze water, and make hydrogen gas that way, you end up with less energy at the wheels of a car than you would just charging a battery from the same solar energy.

    So you have to ask yourself, who benefits from multi-billion dollars of investment into a Hydrogen energy infrastructure?

    --
    How's my programming? Call 1-800-DEV-NULL
    1. Re:The fundamental issue with Hydrogen... by mprinkey · · Score: 4, Interesting

      The key issue with hydrogen is that there is no good way to store it. It diffuses through everything, so leaks will always be an issue. Liquifying takes super cold temperatures and is very expensive. Compressed hydrogen needs to be a ~1000 psi to get a sufficiently high energy density...and that will make for one interesting car crash.

      The best solution for transportable, stable, environmentally friendly fuel is probably methane. Compressed natural gas vehicles are very common. We can make methane about as easily as we can make hydrogen or oil or even from coal, via gasification. All fuel cell manufactures are also looking at reforming mechanisms to make methane useful in fuel cells. As engineer who has worked on fuel cell technology for the last five years, I think it is pretty clear that for future of transportation applications of fuel cells...particularly hydrogen-only systems...is very bleak.

      Fuel cells will be used (eventually) in stationary power systems and very soon in portable electronics that will use liquid methanol as a fuel. Everything else is just a pipe dream, IMO.

    2. Re:The fundamental issue with Hydrogen... by Phanatic1a · · Score: 4, Interesting

      Compressed hydrogen needs to be a ~1000 psi to get a sufficiently high energy density...and that will make for one interesting car crash.

      Ah, come on.

      Gasoline has an energy content of 45 megajoules per kilogram, or 56 MJ per liter. Energy density of hydrogen is about 11 kilojoules per liter.

      My car gets about 325 miles on a 16-gallon tank, so that's 60 liters of gas, or about 3400 megajoules. To get that same amount of energy from hydrogen, I'd need 309100 liters of the stuff, at STP. To fit that into a 16-gallon tank, I'd need to pressurize it to about 5000psi, or about 340 atmospheres.

      Not particularly difficult to build a tank that can hold that. Not even particularly difficult to build a tank that can hold that and still have a huge safety margin. HY80 steel, ferinstance, has a yield strength of (surprise!) 80,000psi on a one-inch thickness. Even aluminum might do the job; 5083 H-116 plate has a yield strength of 34,000 psi. Sure, you're carrying around a tank of highly-compressed hydrogen, but making a tank that's strong enough not to rupture in approachingly-normal circumstances, and connecting it to the car with a strong enough leakage that it won't break itself free and go flying into the next county if it *does* happen to rupture is hardly a game-breaker. Hell, cars today carry around tanks of a highly-flammable liquid in a tank of thin sheet steel, and those rarely rupture, and people aren't concerned about the safety of it.

      No, the key issue with hydrogen is that there's no good way to produce it. Until you go all-nuclear, electrolysis is ridiculously expensive, and steam-reformation of hydrocarbons doesn't really help you.

      Leaks? Get the production cost low enough and nobody'll care about leaks, anymore than they care about the trickle of water leaking from a car's exhaust pipe.

  3. Sadly, we've built a North American wasteland... by Dzimas · · Score: 5, Interesting

    I went shopping this morning - spent my time shuttling my car between various big-box stores. WalMart, the grocery store, the bank. I've got a 2 year-old, so walking is out of the question (and, honestly, I wouldn't want to walk that distance anyway). The truly sad thing is that the shops are "next to each other" but separated by huge expanses of parking lot. What makes it truly sad is that there is an LRT line that runs through the shopping district, with a stop at 2km intervals. Too far for anything but waiting for the busses (which run on a 45 minute schedule on the weekend). My point? Its nearly impossible not to have a car, and each of the free-standing houses in the surburban neighbourhoods is approximately 2000 square feet. Most are at least 2km from shops, schools, and rec centres. I doubt many residents want to live in the area, but we cannot afford expensive "trendy" inner city homes. And the developers seem stuck in a rut -- they just churn out more sprawl each year. I wonder if its possible to make them change? Signed, Sad is Suburbia.

  4. Re:Diodes by ericpi · · Score: 4, Interesting

    The watt-hour meters used by electric companies are supprisingly accurate, and resiliant to many types of 'cheats'. I've heard of several schemes to fool meters, such as drawing lots of power in very short bursts, in hopes that the meter can't keep up, etc. The results I heard were the same: The meter will do a reasonably good job of measuring your energy usage, reagardless of how you choose to use that energy.

    Sure, the the diode you suggest will make your meter run slower... at the mere expense of a bulb that's not as bright as it was before. (Standard light dimmers work in much the same way: By reducing the % of the cycle the bulb is powered.) Aside from the time you spent, you'll simply come out even in the end.

  5. The answer for cars is plug-in hybrids by Thagg · · Score: 5, Interesting
    A group of people called PriusPlus have just about completed a plug-in modification of one of their 2004 Priuses. It is a great car, and a great way to save energy -- at least a good way to save gasoline.


    The normal Prius uses its battery pack to help acceleration, hill climbing, and to power accessories. The battery pack is recharged by the gas engine and by regenerative braking. Every place except North America, the Prius has an EV button, which turns the car into a pure electric car -- but only for a mile or two before the battery reaches a state-of-charge (SOC) that is too low. The Prius battery back is designed to last an extremely long time (warranteed for 150,000 miles), and one way Toyota assures that is by limiting the SOC to a small range, from about 25% full to 80% full.


    Priusplus is adding a separate "traction" battery, that works with the normal Prius drivetrain, to provide a long-distance EV mode. In their first proof-of-concept car (which should be finished this weekend) it uses 12 motorcycle Lead-Acid batteries, and it should go about 20 or 30 miles on an overnight (or overday) charge. Using far superiour Lithium Ion batteries, they should get about 80 miles for a battery pack that costs about $5,000 or so (although current Lithium cells are quite small indeed, requiring a rediculous number of batteries wired into a large pack)


    If I could go, say, even 40 miles on a charge, I wouldn't use the gas motor in my Prius except to climb very steep hills during the week. I'd effectively get well over 100 mpg (Electricity costs, even in California, give a price-per-mile of about 2 cents. Unfortunately, at this point, the cost for the traction battery (because it is more deeply cycled it doesn't last as long) probably adds another few cents/mile.


    PriusPlus is hoping to display there car at a show here in Los Angeles at the end of the month, and is attempting to persuade Toyota that this is a car they should build. Once people are educated about the benefits of hybrid technology, it should be a small step to show them the further benefits of plugging them in.


    I fervently hope that PriusPlus will succeed!


    Thad

    --
    I love Mondays. On a Monday, anything is possible.
  6. Insulate..... by ge · · Score: 5, Interesting

    I live in Tucson, AZ, in a 2500 sq. ft. house, with lots of windows. The electric bill runs about $150 in the middle of summer, $60-$75 in winter. I do have 2 PCs and various other equipment running 24/7.

    Friends who live in a 2000 sq. ft. home built by a volume builder pay about $300 right now, and I have heard of people that have $600/month power bills.

    We spent a few $1000 extra to get a more efficient house:
    - blow-in insulation was used everywhere. There's more than a foot of the stuff under the roof, and 6 inches in the walls, packed tight.
    - most windows are dual-pane Low-E2, tinted to reduce glare
    - we limited the number of skylights
    - the A/C is a high-efficiency, dual-compressor model (18 SEER)
    - we use fluorescent lights where possible
    - we keep shades drawn in rooms we don't use, such as a guest room, and my office on weekends.

    It looks like we'll recover the extra cost in about 5-7 years.

  7. Blankets not always helpful. Go tankless! by raygundan · · Score: 4, Interesting

    Most modern water heaters already have the equivalent of the insulation blankets people put on older models. A recent model will not benefit from the blanket nearly as much as an older unit. More insulation always helps, but the gains become very small after a while.

    A quick reference on when to use or not use the blanket. Anybody reading this should note that the original poster's "warm to the touch test" is absolutely correct-- if it isn't warmer than the surroundings, it isn't losing much heat.

    What you REALLY want to fix this "keeping a tank of water warm all the time" problem is an on-demand water heater. They're a little more expensive than normal water heaters, but they have a few key benefits:

    1. No tank to take up space.
    2. Never runs out of hot water.
    3. Doesn't have to keep a tank of water warm when not in use, making them much more efficient.

    I'm surprised that #2 alone hasn't made them the de-facto replacement for tank water heaters in America (I understand they're common in europe and japan). Energy efficiency aside-- you can't run out of hot water with a tankless, on-demand water heater!

    If you're even *considering* a new unit in the near future, go tankless! Installing them isn't any different than anything else that needs plumbing for water and gas-- even if they've never heard of one, your local contractor will be able to install it.

  8. Re:You forget about nuclear power by El+Puerco+Loco · · Score: 4, Interesting

    There are plenty of people at risk from decaying hydroelectric infrastructure. Dams don't last forever and when they fail the results can be catastrophic. The Chernobyl accident killed 32 people. With the exception of an increase in thyroid cancers, the dire predictions of a massive epidemic of cancers and leukemia have largely failed to materialize. Now consider the Johnstown flood of 1889. More than 2200 people were killed outright as the result of a dam breach. In more recent times, nearly 10,000 people were killed in 1973 in China alone as the result of dam failures. Huge, expensive hydroelectric dams in the U.S. are in danger of being rendered useless as a result of silting, many after a service life of only 50 years or less, and the problem is nearly impossible to fix without breaching the dam and starting over. Hydroelectric dams are responsible for depleting fish stocks and generally wreaking havoc on both down and upstream ecosystems. Hydropower is hardly environmentally benign nor is it entirely safe for communities near large projects. Hydropower has killed more people than nuclear energy (not counting, of course, the bombings of Hiroshima and Nagasaki) has or is ever likely to, but I guess people just feel more comfortable being killed by something familiar that they can see, like a 50 foot wall of water than by a mysterious, invisible force like nuclear radiation, even if the former is far more likely.

  9. Re:You forget about nuclear power by ChumpusRex2003 · · Score: 5, Interesting

    Don't forget that energy can be massively multiplied with suitable reactor technology (i.e. breeders). A fully recycled breeder reactor system could obtain 50x as much energy from the uranium. The same could be done with thorium - except that thorium is 3-4x as abundant as uranium in coal. The total energy resource of nuclear materials in coal, exceeds the energy content of the coal by more than an order or magnitude.