Energy costs - comparison

[mdodson]

From one of the papers in "Solar Power Satellites" (Wiley, 1998) - currently unavailable from Amazon:<br /><br />"The energy to put a given mass in LEO is surprisingly low: some 10 kilowatt-hours per kilogram of payload. This is about the same as the energy per unit payload to fly across the US by commercial airliner. Two reasons that spaceflight is so expensive is the army of engineers and scientists required for a successful launch and the fact that much of the launch vehicle and / or tankage is thrown away each flight. Aware of this issue, NASA has studied ways to reduce launch costs by at least a factor of ten from the present $22,000/kg of the Space Shuttle[23]."<br /><br />I don't intend to stir up lots of well-traveled arguments, but was interested in several ratios. I paid $.07+ per kilowatt hour on my last electric bill. I can get a ticket from DCA to SFO for $5/kg for me and my luggage. So energy is a small fraction of the total cost. The difference between Shuttle and airline operations is a factor of 4400, currently. (whistling)

 

[owenander]

except it takes a lot more energy to fly to space then to SFO?

 

[webtaz99]

Spacships don't (currently) use electricity to boost into orbit. <img src="/images/icons/rolleyes.gif" /> <div class="Discussion_UserSignature"> </div>

 

[josh_simonson]

LOX is made with electricity, and LH2 can be (though it's usually made by reforming natural gas).

 

[MeteorWayne]

Everytime I see electric rates I go nuts. We pay $0.14 per kwh in the winter, almost $0.20 for anything above subsistance level (600 kwh per month) in the summer.<br /><br />It doubles the price of going into space ( <img src="/images/icons/wink.gif" /> ), or driving an electric car! <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[nyarlathotep]

I hear that google and microsoft are buying hydroelectric power for their new datacenters at just under 0.025 USD per kilowatt hour.<br /><br />Offpeak power costs about 0.045 USD per kilowatt hour over here in Australia.

 

[mdodson]

Your remind me of the proposal several years ago that people ought to locate data centers on Alaska's North Slope. (laughing) Lots of natural gas nearby, plenty of cooling, and with a big enough network connection why would customers care about the physical location?

 

[nyarlathotep]

Well, natural gas at current market prices is way too expensive to use for baseload generation.<br /><br />Using a nearby lake for your cooling would be interesting though, I'm sure Yahoo, Microsoft and Google have thought seriously about it. Half your typical power use in a datacenter is HVAC, you could save a fortune by simply dumping all that waste heat into a nearby reservoir.

 

[nexium]

As you typed, energy costs are often tiny compared to miscellaneous, otherwise we could hire a taxi for five cents per mile. In the case of a rocket we lift the mass of the fuel, and missle as well as the payload. The fuel cost is a small percentage of the cost of the missle, even though it far outweighs the pay load. Neil

 

[MeteorWayne]

The fish might not be very happy, though. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[josh_simonson]

Actually, fish congregate around warm water effluents (as long as they aren't polluted).<br /><br />If you wanted to use water for cooling, you could do it along an irrigation canal (at least in california) and the farmers won't care if you heat it up a few 'F. The fish in it are already screwed.

 

[MBA_UIU]

What you really need to compare is not the amount of energy required but the cost to produce that energy. Look at it like this...even though you only need to refuel a nuclear reactor ever 25 years it still cost more per KWH then a hydro dam which has to be "refueled" by a running water supply. Though both produce the same end product they come about it in two completely separate fashions. <div class="Discussion_UserSignature"> <p><strong><font color="#0000ff"><br /><br /> <br /><img id="268587ce-7170-4b41-a87b-8cd443f9351a" src="http://sitelife.space.com/ver1.0/Content/images/store/6/8/268587ce-7170-4b41-a87b-8cd443f9351a.Large.jpg" alt="blog post photo" /><br /></font></strong></p> </div>