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Thread: Alternative Energy Reality - It's A Numbers Game

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    Alternative Energy Reality - It's A Numbers Game

    Let's face it - who hasn't heard of a dozen ideas for alternative energy being touted as "the one" over the last few decades? Nuclear and Geothermal was going to save everyone because it was "inexhaustible." Then solar energy was the saving grace, as it's "replenishible." Now Wind energy mills are being erected at breakneck pace. Another thread here discusses oil from algae that's a near one-for-one replacement for diesal fuel.

    Enough of the hype, already!

    Enter David MacKay's Commentary.

    Don't get me wrong - I don't like wind power. I think that thirty years down the road we'll discover wind power alters the surface ecology as much as hydroelectric damns alter river ecology. Solar power, however, I like. I mean, why allow all that sunshine to heat the roofs, attics, and living spaces of houses in the summertime when it can be converted to electricity used to cool them, instead? And so far as combatting global warming goes, the only thing that's more effective than converting the solar influx directly into electricity is coating roofs with aluminum foil to reflect it right back out into space. Speaking of which, why aren't we doing that, anyway? Seen any houses looking like thermos bottles in the 115 deg desert heat, lately? Why not? Why unnecessarily absorb that heat then work that much harder to get rid of it? Why not reflect it out in the first place?

    Back to MacKay: He's right, you know - It's all about the math. When you crunch the numbers, the RIGHT answers surface, instead of the politically correct answers (like cutting CO2), or the environmentally conscious answers (like bio-fuels), or the media-hyped answers (like wind power).

    Couple of figures for you, based on numbers, the facts behind this so far as the US is concerned:

    Solar: "To supply 42 kWh per day per person from solar power requires roughly 80 square meters per person of solar panels." That's more than 8,600 square miles, around the area of Vermont or New Hampshire.

    Wind: "To deliver 42 kWh per day per person from wind for everyone in the United States would require wind farms with a total area roughly equal to the area of California, a 200-fold increase in United States wind power."

    Nuclear: "To get 42 kWh per day per person from nuclear power would require 525 one-gigawatt nuclear power stations, a roughly five-fold increase over today's levels."

    By the way - 42 kWh per day is just one-third of the minimal 125 kWh per day per person that might be achieved if we radically change transportion, technology, building construction, and lifestyles. This would require 42 kWh from each of Solar, Wind, and Nuclear.

    Right now, we Americans are burning 250 kWh per person, per day. By contrast, Europeans are using just 125 kWh.

    Boy, do we have our work cut out for us!!!

    In closing, I'd like to make another plug for all-electric vehicles, as they use around 12 kWh per 100 km, as opposed to the average fossil car in Europe, which uses 80 kWh per 100 km.

    "Go to a hydrogen economy!" you say? Yeah, right - "The BMW Hydrogen 7, for example, uses 254 kWh per 100 km."

    So you see - the real solution has nothing to do with the hype. It's all in the numbers...

    Edit: This just in...
    Last edited by mugaliens; 2009-May-18 at 06:51 AM. Reason: Found supportive article

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    He doesn't state what solar efficiency estimate he's using. Solar is probably the best long term renewable if we can get the efficiencies up and costs down. He also oversimplifies the energy needs and their place. Solar PV is one aspect of solar and solar thermal can do some things better, decreasing the kWh/person needed. Both versions of solar can be retrofitted into existing home roofs but for high-power rail, baseline power may need to be used.

    A comparison with Europeans is like apples and oranges, the US is big and spread out. Our cities are farther apart and the distance the average person travels on a daily basis for work and other activities is farther. US cities are larger and have wider streets and so larger vehicles are more common, whereas European cities and denser and often have streets that are too narrow. Moreover, cost for purchase and operation may also be a limiting factor in European propensities for 2-wheeled vehicles. The US might try to replicate some of these things by closing streets and increasing mass-transit.

    Of course, the climate is different and larger extremes in seasonal temperature variations mean higher costs for heating and cooling. Perhaps it just costs more kWh/person to live in the US. Sure, we can retrofit and remodel structures to be more efficient, but that's going to increase the kWh/person cost temporarily while all the material is processed and transported and rebuilt.

    BTW, some of the construction design in the desert is intended to absorb heat during the day is because it gets cold at night... because it's a desert.
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    Putting alunimum foil on houses in the desert?
    Man, that'd be too shiny~ Wouldn't people go blind?
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    Quote Originally Posted by Ara Pacis View Post
    He doesn't state what solar efficiency estimate he's using ... He also oversimplifies the energy needs and their place...
    And he fails to consider market responses to changing demand. Big deal -the point remains: Various forms of alternative energy have been so overhyped by various interest groups that most people haven't a clue as to what they're talking about anymore - so much so that the only viable long-term solution is to do the math - crunch the numbers!

    A comparison with Europeans is like apples and oranges, the US is big and spread out. Our cities are farther apart and the distance the average person travels on a daily basis for work and other activities is farther. US cities are larger and have wider streets and so larger vehicles are more common, whereas European cities and denser and often have streets that are too narrow.
    Having lived in and driven around Europe, I strongly disagree with all of the above except for the fact that we are more spread out. But that alone does not count for the difference in useage rates. Americans will drive across town for that one thing they're looking for when an acceptible version is available down the street. Furthermore, we Americans buy, own, and junk far more household goods (more than double) than your average European.

    Moreover, cost for purchase and operation may also be a limiting factor in European propensities for 2-wheeled vehicles.
    Purchase, no. Operation, yes, due to petrol prices.

    The US might try to replicate some of these things by closing streets...
    Wouldn't work!

    ...and increasing mass-transit.
    Mass-transit isn't cost-effective in areas with lower population density (too spread out). It works (and is often used) in the larger cities, such as NY and San Francisco.

    Of course, the climate is different and larger extremes in seasonal temperature variations mean higher costs for heating and cooling.
    In some areas. Less in others. You'll have to support this statement with weighted means, rather than sweeping allegory or anecdotal evidence.

    Perhaps it just costs more kWh/person to live in the US.
    More than 80% of France's electrical power is nuclear. France sells a lot of power to Germany, which is very opposed to having it's own nuclear facilities.

    Sure, we can retrofit and remodel structures to be more efficient, but that's going to increase the kWh/person cost temporarily while all the material is processed and transported and rebuilt.
    "Temporarily" isn't an acceptable comparison basis. Life-cycle time frames are used for all comparisons of cost, efficiency, etc.

    BTW, some of the construction design in the desert is intended to absorb heat during the day is because it gets cold at night... because it's a desert.
    I've lived in deserts, too. The dry air lacks the thermal blanketing capacity of H2O vapor, allowing greater temperature swings between day and night. Those temperature swings are sufficiently large to capture for both heating and cooling provided such were designed and built into the homes.

    They're not - America's building practices, quite frankly, STINK! A mud hut is better equipped and more thermally efficient than American homes. That's the ONE area where we should have, 50 years ago, mandated certain building practices such as employing thermal mass, to mediate the temperature differences between night and day, and passive solar heating and cooling. Such measures, if routinely employed, would have resulted in efficiencies which were increased not by 5%, nor by 50%, but by 500% over the average existing designs.

    That's where a lot of those kWh are going here in the US - out the window (literally).

    Quote Originally Posted by Cookie View Post
    Putting alunimum foil on houses in the desert?

    Man, that'd be too shiny~ Wouldn't people go blind?
    Sure - but look at the up side - you're house would have the coolest looking tin hat on the block!

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    ...the only viable long-term solution is to do the math - crunch the numbers!
    I crunched some numbers in a post a few months ago. Here they are:
    The ten megawatt Cloncurry solar power station under development in north west Australia has a price tag of $31 million and will operate at an average of about 31% of capacity, producing about 30 million kilowatt hours a year, starting in 2010. It will also store thermal energy in order to provide baseload power. The price per average kilowatt of electrical production is about $10,300.

    The Portland Wind Project will be completed this year in south-east Australia and will produce electricity at a cost of about $4,300 per average kilowatt of output.

    A provisional contract cost for an AP1000 reactor at the Virgil C. Summer nuclear plant in the US is $7.7 billion or $7,300 per average kilowatt of output. The cost of a kilowatt of new nuclear electricity in Vogtle has been contracted at $10,400 or about $12,600 when transmission upgrades are included.
    Changes in exchange rates since then will have slightly altered the US figures. And I will mention that since electricity produced in the daytime is more valuable than electricity produced at night in Australia, the figures for the solar thermal station are better than they appear.

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    Fewer people.

    That's the only number that makes sense to me.
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    Quote Originally Posted by pzkpfw View Post
    Fewer people.

    That's the only number that makes sense to me.
    And it will happen, permanently.

    The only question is how. If it isn't by our own actions directly affecting birth & death rates (such as the cultural, and sometimes legal, shift in some countries toward having fewer children), it will be because of soil erosion, soil cation depletion & salinization, and well water depletion.

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    Quote Originally Posted by mugaliens View Post
    Seen any houses looking like thermos bottles in the 115 deg desert heat, lately? Why not? Why unnecessarily absorb that heat then work that much harder to get rid of it? Why not reflect it out in the first place?
    Not sure if you where quoting him there, but if you where, his ignorance of good thermal design for deserts doesn't bode well for the rest of what he says.
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    Quote Originally Posted by David MacKay
    Right now, we Americans are burning 250 kWh per person, per day. By contrast, Europeans are using just 125 kWh.
    I'll take it that these numbers are correct?

    If memory serves me, energy consumption per capita is depends on two factors:
    1. Real income per capita
    2. Population density

    The US and Europe have comparable incomes, so we can forget about (1). Besides, I'm hope no-one sane advocates poorer Americans as a solution.

    So we're left with increasing (2). You'll note that, paradoxically, increasing population in the US would achieve what David MacKay wants.

    A more practical solution is to tax per head energy consumption in the US. You want less of something, tax it.

    EDIT: Re: 2. Population density. Europe has over twice the density as the US. Exact numbers unknown to me at this point in time.
    Last edited by PraedSt; 2009-May-18 at 04:43 PM.

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    Quote Originally Posted by Ara Pacis View Post
    <snip>
    A comparison with Europeans is like apples and oranges, the US is big and spread out. Our cities are farther apart and the distance the average person travels on a daily basis for work and other activities is farther. US cities are larger and have wider streets and so larger vehicles are more common, whereas European cities and denser and often have streets that are too narrow.
    Yes, but how much of that is given by geography, and how much is given by our own choices. Before WWII, many (most?) Americans (except those living on farms), lived either in cities or in close-in suburbs, and their jobs were mostly in "the city". So mass transit could work, since most routes were short (at least shorter) and were in and out of the central city.

    Today, many (most?) of these same people live in outer ring suburbs and work in outer ring suburbs (I seem to recall some number like only 20% work in central cities). I'll admit, I'm one of them. There is no simple (or even mildly hard) way to set up a rapid transit system for all the different possible suburb to suburb commutes. Americans also change jobs more frequently than past generations, so if you advocate living near your job, then every time I change jobs, I have to move.

    I don't think there is an easy, rapid solution to these. Some how encouraging businesses to move back in closer to the city, having people follow them back in, and creating an environment with a higher density, would help. But since it took about 60 years for us to get into this situation, it wouldn't be solved quickly.
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    Here is a table from the US Dept. of Energy. My calculation says his numbers are round-off correct (I get about 260 kwh per person per day, so close enough).

    The by-state rankings also confirm that high population density contributes to use efficiency. Note that New York State and California are the second and fourth most-efficient states per capita, reflecting the higher efficiencies of energy use in dense urban areas. Per capita energy usage in New York City is about 14 kwh.

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    This might help.

    Higher CAFE standards, 4 years early. Just a small press release, so I've copied it all below. Note, current standard is 27.5mpg for passenger cars.

    The Obama administration is expected to direct the Environmental Protection Agency and the Department of Transportation to jointly raise fuel-economy standards and reduce greenhouse-gas pollution.

    The plan calls for raising the overall fuel economy of automobiles to 35 miles a gallon by 2016, four years faster than federal law requires, people familiar with the matter said Monday.

    As part of the agreement, the state of California has agreed to "stand down" from its effort to implement its own greenhouse gas emissions standards for automobiles, one person familiar with the matter said, since the new federal rule would be as stringent as the state's standard.

    An announcement of the agreement is expected Tuesday. A 2007 energy law requires auto makers to achieve fuel economy of 35 mpg no later than 2020.

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    Quote Originally Posted by PraedSt View Post
    This might help.

    Higher CAFE standards, 4 years early. Just a small press release, so I've copied it all below. Note, current standard is 27.5mpg for passenger cars.
    I used to own a VW Rabbit diesel that got 48 mph.

    It was a 1979 model.

    I'd say the "higher" standards are WAY, WAY too low, particularly as I used to haul all my stuff to and from college each year in that thing!

    At around 70 mph... Uphill... With the load...

    And now the "goal" is 42% less?



    Who's kidding who, here!

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    Quote Originally Posted by mugaliens View Post
    I used to own a VW Rabbit diesel that got 48 mph.
    That's a Golf when it's not in America, right?

    WolframAplpha tells me 48 mpg is 20 km/l. Not bad. This would be because of (1) European car and (2) diesel?

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    I've been thinking this for several years now: what if everyone in the world were required by law to paint their roof white?

    Whilst we're at it, there could be surface coatings applied to road surfaces to raise the albedo.

    I've never done the maths but I bet this could be a major factor in controlling global warming.

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    Quote Originally Posted by PraedSt View Post
    This might help.

    Higher CAFE standards, 4 years early. Just a small press release, so I've copied it all below. Note, current standard is 27.5mpg for passenger cars.
    I heard a bunch of bad reporting on this change, this morning on the radio. They kept announcing that all cars would get at least 35 mpg. Unless they changed things, that is not how the CAFE standard works. The 35 mpg is a fleet average, not a minimum.

    It should also be noted, that because of pressure from the auto industry, they were not changed for years. From this website:
    Originating in 1975, CAFE standards were intended to reverse a trend toward worse gas mileage, which had fallen to 12.9 miles per gallon (mpg) in 1974. The new standards mandated 18 mpg in 1978 models, rising to 27.5 by 1985.
    ...

    Some ten years after inception, CAFE standards began a period of reduction. As the oil crisis gave way to a long period of surplus, larger vehicles became increasingly popular. Responding to appeals from automobile manufacturers, the federal government decreased CAFE standards from 27.5 to 26 mpg for 1986 model passenger cars, a number that was restored to 27.5 in 1990, where it remains today.
    So, from 1985 to now, there was no mandate to raise full efficiency.
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    Quote Originally Posted by mugaliens View Post
    And he fails to consider market responses to changing demand. Big deal -the point remains: Various forms of alternative energy have been so overhyped by various interest groups that most people haven't a clue as to what they're talking about anymore - so much so that the only viable long-term solution is to do the math - crunch the numbers!
    And your and his point is what exactly? The admonition to crunch numbers still leaves your and the author's conclusions unconcluded. Is there an energy bottleneck? Do you want people to use less energy? Do you want people to keep burning more fossil fuel? Do you want people to stop beliving in hyper because hype is deleterious in some yet to be explained manner? I don't understand the point of your rant. Surely anyone smart enough not to draw to an inside straight can see that incresing efficiency and using less energy is a good thing. But you and the author seem to be pointing to the Europeans and saying: they are different from Americans.

    Having lived in and driven around Europe, I strongly disagree with all of the above except for the fact that we are more spread out. But that alone does not count for the difference in useage rates. Americans will drive across town for that one thing they're looking for when an acceptible version is available down the street. Furthermore, we Americans buy, own, and junk far more household goods (more than double) than your average European.
    Acceptable by whom? surely You aren't saying that a Zune is an acceptable substitute for an iPod? Or do you mean price? What do you mean? Does not junking a less efficient appliance for a new one that is more efficient help lower the kWh/person?

    Wouldn't work!
    Yes, rather my point.

    Mass-transit isn't cost-effective in areas with lower population density (too spread out). It works (and is often used) in the larger cities, such as NY and San Francisco.
    Yes, which is part of the circumstance of the US being more spread out. I don't know if it's important to go into why Americans are more spread out, other than the ability of the geography being conducive to it (but racism and the Cold War are some of the other reasons).

    In some areas. Less in others. You'll have to support this statement with weighted means, rather than sweeping allegory or anecdotal evidence.
    Why? My point is that the assumed average of kWh/person may ignore such important points. I'm asking you to clarify and break down your evidence and introducing ways in which you can.

    More than 80% of France's electrical power is nuclear. France sells a lot of power to Germany, which is very opposed to having it's own nuclear facilities.
    And this has what do to with how much more it might cost in kWh/person to live in the US?

    "Temporarily" isn't an acceptable comparison basis. Life-cycle time frames are used for all comparisons of cost, efficiency, etc.
    Perhaps this illustrates the problems of your sort of thinking. Averages are all well and good, but remodelling requires future-present expenditures of energy that may just not be available due to the limitations in energy suggested by the initial article. And "temporary" isn't especially short-term for retrofit projects may occur over the course of decades sucking up precious kWh.

    I've lived in deserts, too. The dry air lacks the thermal blanketing capacity of H2O vapor, allowing greater temperature swings between day and night. Those temperature swings are sufficiently large to capture for both heating and cooling provided such were designed and built into the homes.

    They're not - America's building practices, quite frankly, STINK! A mud hut is better equipped and more thermally efficient than American homes. That's the ONE area where we should have, 50 years ago, mandated certain building practices such as employing thermal mass, to mediate the temperature differences between night and day, and passive solar heating and cooling. Such measures, if routinely employed, would have resulted in efficiencies which were increased not by 5%, nor by 50%, but by 500% over the average existing designs.

    That's where a lot of those kWh are going here in the US - out the window (literally).
    Ah, good, you do understand. I agree they should change building styles, but that costs kWh. Are you primarily concerned with single-household dwellings? What about high-rises?
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    Quote Originally Posted by PraedSt View Post
    That's a Golf when it's not in America, right?
    No, in the USA, Golfs are either Golfs or GTIs. A Rabbit is similar but slightly longer and heavier. VW classifies both of them as "compact" and publishes very close fuel efficiency ratings for both but a tiny bit lower for Rabbits.

    Both are smaller and lighter than most other car models in the USA. In the past, they might have been even lighter than now due to less demanding crash safety requirements, but I don't have a way to check on that.

    Diesel always goes farther for the same number of gallons of fuel.

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    Quote Originally Posted by mugaliens View Post
    I used to own a VW Rabbit diesel that got 48 mph.

    It was a 1979 model.

    I'd say the "higher" standards are WAY, WAY too low, particularly as I used to haul all my stuff to and from college each year in that thing!

    At around 70 mph... Uphill... With the load...

    And now the "goal" is 42% less?



    Who's kidding who, here!
    MPH? I assume you mean MPG. BTW, does VW make vehicles with lower MPG? If so, then even VW's fleet average is less than 48.
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    I've been thinking this for several years now: what if everyone in the world were required by law to paint their roof white?

    Whilst we're at it, there could be surface coatings applied to road surfaces to raise the albedo.

    I've never done the maths but I bet this could be a major factor in controlling global warming.
    Here is a blog post on the subject:

    http://climateprogress.org/2009/01/0...on-cool-roofs/

    It appears to be one of the more cost effective methods of mitigating global warming.

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    Quote Originally Posted by Swift View Post
    Yes, but how much of that is given by geography, and how much is given by our own choices. Before WWII, many (most?) Americans (except those living on farms), lived either in cities or in close-in suburbs, and their jobs were mostly in "the city". So mass transit could work, since most routes were short (at least shorter) and were in and out of the central city.
    I seem to recall that it was only recently, as in the last year or so, that the majority of Americans were living in the urban environment. Previously, the majority of the US population resided in rural settings, either on farms or isolated homesteads or small towns and villages. I think geography and the automobile are key factors in the ability for the US population to spread out, but the motivations may be various. Previously, a lot of the growth might have been along train routes, however, that may not be accurate either as farm families may have been more prolific than city-dwelling families for various reasons.

    Today, many (most?) of these same people live in outer ring suburbs and work in outer ring suburbs (I seem to recall some number like only 20% work in central cities). I'll admit, I'm one of them. There is no simple (or even mildly hard) way to set up a rapid transit system for all the different possible suburb to suburb commutes. Americans also change jobs more frequently than past generations, so if you advocate living near your job, then every time I change jobs, I have to move.
    Mass transit, maybe; rapid transit, maybe not. Chicago's Metra rail (not to be confused with the famous intra-city El) is a spoke-and-hub style of mass transit for commuters using regular train lines and diesel locomotives, and it works well. Howeover, you're right that it doesn't do well moving from one suburb to another since you'd have to go to the hub and out on another spoke. What may be needed are circle routes that trace arcs around the central city and between suburbs. Maybe other cities do this but not the RTA (Regional Transit Authority around Chicagoland).

    I don't think there is an easy, rapid solution to these. Some how encouraging businesses to move back in closer to the city, having people follow them back in, and creating an environment with a higher density, would help. But since it took about 60 years for us to get into this situation, it wouldn't be solved quickly.
    I wouldn't want to get political or racial, but there have been some attempts in some communities to reinvest in the inner-city and bring back businesses and the more affluent residents via beautifification and other reinvigoration projects that take the place of previous "projects".
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    Quote Originally Posted by Swift View Post
    They kept announcing that all cars would get at least 35 mpg. Unless they changed things, that is not how the CAFE standard works. The 35 mpg is a fleet average, not a minimum.

    It should also be noted, that because of pressure from the auto industry, they were not changed for years.

    So, from 1985 to now, there was no mandate to raise full efficiency.
    Right, I keep forgetting CAFE is fleet average.

    As for standards not increasing, there was definitely pressure from industry. That article you link also mentions another of their 'tactics'- gaming the rules.
    Manufacturers, however, have been able to apply more lenient standards through the light truck exception...

    The basic definition of a light truck--any truck or truck derivative with a gross vehicle weight rating of 8,500 pounds or less--allows plenty of room for family vehicles. Because light trucks is considered a separate category from passenger automobiles, vehicle manufacturers have been able to build and market SUVs and other large vehicles with a less stringent CAFE standard
    Ingenious!

    To be fair, CAFE standards were a response to higher oil prices in the 70s. Once that went away, there was less pressure to economise. Probably the Govt and the public just couldn't be bothered any more- it was just easier to go along with whatever the auto industry proposed.

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    Quote Originally Posted by Delvo View Post
    No, in the USA, Golfs are either Golfs or GTIs. A Rabbit is similar but slightly longer and heavier.
    But, but, but...they look the same!

    No wait, one's black and the other's white.

    Thanks for that.

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    Quote Originally Posted by Ronald Brak View Post
    Here is a blog post on the subject:

    http://climateprogress.org/2009/01/0...on-cool-roofs/

    It appears to be one of the more cost effective methods of mitigating global warming.
    They also mention loads of trees have to be planted. I can see that this will be difficult, especially in central business districts- but I say go for it. Sounds like a wonderful idea. Could do with more trees.

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    Quote Originally Posted by PraedSt View Post
    They also mention loads of trees have to be planted. I can see that this will be difficult, especially in central business districts- but I say go for it. Sounds like a wonderful idea. Could do with more trees.
    I'd like to see a fight by white-roofies against green-roofies. Chicago is a hotbed of green-roofing, with lots of buildings putting plants, if not trees, on their roofs.
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    Quote Originally Posted by Ara Pacis View Post
    I seem to recall that it was only recently, as in the last year or so, that the majority of Americans were living in the urban environment. Previously, the majority of the US population resided in rural settings, either on farms or isolated homesteads or small towns and villages.
    According to this from the Census Bureau, as of the 2000 census, the urban population of the US was 79% and the rural population was 21% (more detals at that link).

    This website from Hofstra University has graphs of % urban population over time by continent. Even in 1950, North American was over 60% urban.
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    Quote Originally Posted by Swift View Post
    According to this from the Census Bureau, as of the 2000 census, the urban population of the US was 79% and the rural population was 21% (more detals at that link).

    This website from Hofstra University has graphs of % urban population over time by continent. Even in 1950, North American was over 60% urban.
    I'm not sure how to read that, and can't tell where they draw the line between living in a large city and not living in a large city. Depending on who you talk to, "small towns" can include cities with populations on the order of tens of thousands.
    Et tu BAUT? Quantum mutatus ab illo.

  28. #28
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    Yes, the shift happened in the 1940's, although it was beginning in the 30's. It's interesting that the rural population has shrunk somewhat (say, 15%) over the last century, but the urban has increased by a factor of 10.

  29. #29
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    Census Bureau definition of urban (metropolitan) given here; try page 32, I think.

  30. #30
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    Quote Originally Posted by mugaliens View Post
    In closing, I'd like to make another plug for all-electric vehicles, as they use around 12 kWh per 100 km, as opposed to the average fossil car in Europe, which uses 80 kWh per 100 km.
    The main reason that all-electric vehicles use less energy is that they are deliberately constructed to use less energy, not because they are electric. If one built fossil-fuel-powered vehicles of the same weight and performance characteristics, they would be a lot more fuel-efficient. Though not quite as efficient as the electric vehicles because electric motors are more efficient than small internal combustion engines, though with turbo-diesels the difference is getting smaller. When one takes into account the very considerable cost of the making the electricity storage system in an electric car, and the large losses in making the electricity, transmitting it and storing it into the on-car storage system, I think that fossil-fuel-power in small light-weight vehicle would be more carbon efficient than electric power.

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