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window-unit generator

city-dwellers' backup power source uses natural gas
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Having an alternative power souce will probably become more important to city-dwellers after the recent blackout in the northeast US. Honda and others make small generators, but these require frequent refueling and unleaded can be difficult to get hold of in a crisis. What we do have plenty of here in NYC is natural gas; but the smallest nat gas powered backup generator I could find provides 6kW and weighs 450 pounds, a bit much for my 400sqft apartment. How about a small (1-2kW), nat gas fired generator mounted in a "window unit" air conditioner frame? The only downside I can see is product liability problems due to morons who don't know to turn off the gas before trying to do the self-install.
yabbadab, Aug 16 2003

real solar electricity (not PV) http://www.solel.com
Someone should take up their marketing now in the US [pashute, Oct 17 2004]

Domestic CHP system http://www.niesmart.co.uk/dchp.htm
Or one of these? [moomintroll, Jul 26 2006]

[link]






       ... and the fumes coming into the window on the 20th floor from the 19 units below running natural gas generators.
Cedar Park, Aug 16 2003
  

       had a small natural gas generator once. it was a modified gasoline generator. i think all it needed was i different carburetor. not window mounted, mind you.
swamilad, Aug 16 2003
  

       The fan in our furnace at home is powered by a natural gas motor so, it's not a completely unheard of approach. I like the idea but do wonder about whether people could safely install such a thing; not only the gas connection but the exhaust system as well so that it didn't get swept back into the room.
bristolz, Aug 16 2003
  

       One thing which would help prevent electrical problems such as those experienced recently in NY/NJ/PA/OH/Ont, and those experienced in the past in CA, would be to encourage businesses that have adequate backup generation facilities to use them when power demand is tight. After all, every KW generated by buildings or businesses is a KW that doesn't have to come from somewhere else.   

       Many people don't realize it, but the costs to generate electricity are highly variable. Some plants can produce electricity for a marginal cost of under $0.01/kWh but (1) have high fixed costs, whether they're producing a lot of electricity or a little; (2) cannot be ramped up or down quickly. Other plants can go from zero to full production in a few seconds, but are very inefficient and have marginal costs of $0.50/kWh or more.   

       Electric companies try to use efficient plants as much as possible, and inefficient plants as little as possible, but when power demand is high, they end up having to use all their plants. In such cases, every kW that customers could produce themselves (or do without) would save the power plant $0.50 or more.   

       The window-unit generator is a cute extension of this concept, but I really don't think it's quite practical. If left connected permanently, it's going to be an eyesore. If only installed as needed, moving around the gas line will create an explosion hazard.
supercat, Aug 16 2003
  

       [supercat] Diesel generators are really only used for periods of electrical failure. Are you suggesting that companies should use them gratis when the local Electricity Board says that they are about to fail in their job of providing electricity?. We have some solutions that can mitigate the effect of a power dip in a commercial building. If we were to be told to do so, who would pay??
gnomethang, Aug 16 2003
  

       gnomethang: The idea would be that customers receive a discount on their electrical usage in exchange for not using any externally-supplied electricity during times of peak demand.   

       reensure: I'd like to see some migration toward a system where communities had their own 'peaker' plants to tide them through electrical shortages. Although peaker plants are inefficient, they have relatively low construction and fixed costs, and their ability to come on-line quickly would allow them to buffer momentary demand surges.   

       I would expect that a community with a peaker plant would be able to negotiate a substantial discount on grid power in exchange for being able to be thrown off-grid on short notice. Although the peaker plant wouldn't be very energy-efficient while meeting demand surges, it would be no less efficient than a peaker plant located on the grid many miles away. Actually, the reduced transmission-line distance might make it more efficient.
supercat, Aug 16 2003
  

       //Any chance one of these peakers didn't 'play by the rules' we heard of and overloaded some transmission lines?//   

       I wouldn't expect so, since everything that's connected to the grid is tightly regulated (in both senses of the term). Actually, the cascading failure suggests to me that a few more peaker plants might be a good thing; they're quite cheap per unit of capacity, so it should be reasonably economical to have enough peakers that they're seldom used to anywhere near capacity.   

       BTW, one thing that would improve the electric industry immensely would be to have customer metering units which could shed load in times of shortage. Customers who were willing to have their load cut under certain terms would be entitled to a discount on their electric rates. If managed load shedding were implemented, it could help mitigate the catastrophic effects seen last Thursday. It would also provide incentives for power companies to improve their infrastructure, and would allow customers to balance price versus reliability.   

       I would expect that many customers would be willing to accept occasional 15-minute outages if it meant they could get a substantial discount on their electric bills. It would mean they'd need to get UPS's for their computers and VCR's, and install/replace backup batteries in their clocks, but if offered a discount many customers would accept the inconvenience. Some wouldn't, of course; they'd get more reliable power but have to pay more for it.
supercat, Aug 17 2003
  

       [jurist] I meant "have their load CUT" and edited by anno to say that.
supercat, Aug 17 2003
  

       Nicely half-baked! It almost sounds like a reasonable idea until you think about it. Natural gas of all things... NG does not liquefy like propane so we would be hauling heavy expensive high-pressure cylinders around inside the building, and a lot of them since they don’t hold much for their size. Yet the exploding building trouble is only a comparatively minor drawback. Your punch line / basic fallacy is “What we do have plenty of here in NYC is natural gas”.
Fussass, Aug 17 2003
  

       Allow me to clarify: In New York City at least, stoves, hot water heaters and home heating systems are almost 100% run by natural gas LINES which run directly into the home / apartment block. When I say we have "plenty" of natural gas, I mean it's easily available to almost every home simply by tapping into the existing line which runs to one's rangetop/oven. No CNG bottles necessary. Apologies for the confusion.
yabbadab, Aug 17 2003
  

       No apologies needed, just my ignorance of NYC customs. All right then, no exploding buildings.
I would like point out though that there is no gas in NYC. What you have there is a pipe with gas coming out of it. I have been around the other end of that pipe, and I can tell you that it is a loosing battle trying to find enough to put in. The day we can’t, it will stop coming out of your end. A large part of your electricity is generated in gas-fired plants. If you are not expecting this you are going react all at once, probably in some unfortunate way.
If you could get the people in a building together on it, there is a proven technology for building survival, co-generation. It consists of a diesel engine that will run on either NG or stored heating-oil driving a generator. All the heat produced is collected for the building. In winter the electricity is basically free and will keep things going until the grid is restored. One central unit will be less expensive, more efficient and safer than the individual approach. Variations of these in any size are available as stock items.
Fussass, Aug 17 2003
  

       OK, this is a 'what if' technical question, partially, but not totally un-related to the intended purpose of the posting:   

       Restoring power to a large area is much like the initial powering-up of a large transformer. The 'in-rush' amperage required to restore service to a large electrical system is roughly 150-200% of the average amperage draw for the system it serves, which requires the electrical generating facilities to provide an initial capacity of an extraordinary amount. This is what makes it so difficult to get a system of this size back 'online'.   

       If this type of device were widely-installed, (perhaps less conspicuously than in one's window, and possibly subsidized by the power companies?) might one be able to synchronize this generator to the wave of the grid (I suppose with some sort of governing device, ie: a simpler form of the Woodward UG-8) with this unit and then throw the switch and then push the throttle full-open (essentially throwing all excess power into the local electrical grid, while maintaining power on an individual level) to assist as a 'surge buffer' to help the power companies in the effort to restore services?
X2Entendre, Aug 18 2003
  

       [X2] Synchronization is possible, Enercon invented it for windmills. The system is for lots of individual units running at variable power. However, a US company (Kentech), got it patented in the US after that (USPTO 5,083,039). Kentech failed and Enron got the patent. Enron, never used it and when it failed General Electric got the patent. GE is the only company in the US allowed to use this technology, but their actual implementation (at least for windmills) stinks. Their gas driven generator will probably be of similar quality, if they do it at all. Summary; for the next decade(s) the synched generators will probably be wishful thinking.
kbecker, Aug 18 2003
  

       For supplemental generation use, synched generation could be accomplished using a squirrel-cage unit running at slightly over synchronous speed. Such units are naturally self-synchronizing to a supplied waveform, they require some additional circuitry to operate in the absense of externally-applied voltage.
supercat, Aug 19 2003
  

       bristolz,   

       Your furnace fan is powered by a natural gas motor? Where can I get something like this? This would be great during winter power failures.
BMCCUE, Jul 25 2006
  

       You picked a bad time to ask [bz] a question.
angel, Jul 25 2006
  
      
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