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Another Step Forward In Small Scale Electrical Generators
NicknamesAreStupid writes "Product Design & Development reports another breakthrough in small scale solid oxide fuel cells. This methane-fueled cell achieves about 50% efficiency at around 2kW, enough to power an average home. It does so by efficiently recycling its heat to perpetuate the process. Of course, this is not practical for most homes, which only have natural gas that contains nearly one fifth impurities. However, that could change if gas suppliers refined their product."
Could it be used on board an electric vehicle to provide power in lieu of a battery?
It must have been something you assimilated. . . .
Hold the phone, 2kW enough for an average home? Well, i'm sorry but i have an average home but 2kW isn't enough for me. I mean, 2000W is just enough power for a small heater.
That should be part of the efficiency calculations as well.
It makes all the machinery frail and brittle. I'll settle for a few percent less with a Stirling engine running off the natural gas we have now. And most likely it will run on anything I throw into the 'boiler'.
“He’s not deformed, he’s just drunk!”
A classic problem with fuel cells is extreme intolerance to contaminants. Even trace amounts of contaminants tend to damage fuel cells. Hydrogen fuel cells need cleaner hydrogen than is normally available commercially. Research continues on making fuel cells more tolerant of contaminants, but it's hard. Fuel cells are surface chemistry systems. 40 years of research hasn't solved this problem.
Reverse osmosis water purification systems once had the same problem. Today they routinely take in raw seawater and pump out clear water. They just need a backflush cycle once in a while to flush the crud off the membranes. Fuel cells aren't there yet.
Until now, the most efficient electric generators for home use I've seen are heat-power coupling devices: natural gas-powered engines that have their coolant loop linked to the house central heating system. They can reach a combined efficiency of near 100%, if you can use the heating. In the summer, they get expensive to use.
60% efficiency for electricity alone is pretty good.
I already have a home source of methane. I just need a nice way to capture it.
now we need to go OSS in diesel cars
Make it run reliably for 2+ years and you got a market. 2KW is small for Canada as if you pull 1lb out of a 100W light thats only about 2K every 8 weeks. Now in the US you're looking at 3000-4000K for that same lb.
by TheSpoom (715771) Uncaring Linux user here. I have nothing to add to this but please continue. *munches popcorn*
what about building them at sub stations?
How effective would methane generators be in small farming communities, which already produce methane as a by-product? If they work well, then they may be able to be off-grid completely?
Jumpstart the tartan drive.
Bullshit
Or pig shit.
Keep livestock,
gather the manure,
make methane.
In our case though the animals spread the manure out in the fields which is far more efficient.
The average American house consumes about 1.5KW electricity average across the days (and nights) through the weeks of a year. But they not infrequently peak demand in spikes over 2KW. A hairdryer or space heater draws about 1.5KW. A dishwasher (especially with extra washing or drying heat boost) will draw 1.5KW. An electric stove/oven can draw 4KW or even 7KW as it heats up. A vacuum cleaner can draw up to 1.5KW, especially if it's a strong one that gets jammed.
And all of those could happen at once. A couple happening at once is pretty likely at least once a year. Plus the rest of the 1KW regular demand, which is closer to 2KW max, averaged against quiet times closer to 0.1KW.
A home power supply should be close to half the 100A 120VAC panel, which is 6KW. A 5KW max supply is probably just fine. A 2KW fuelcell would need a battery that can output 5KW for at least a few minutes, perhaps while an alarm goes off warning the battery will drain down shortly and circuit breakers will snap.
Really all the residential fuelcells I've seen talked about are 5KW. A 2KW fuelcell seems like a good device for a yacht.
--
make install -not war
The image I have of the US does not include 2KW covering the average home. It might do for the 96% of the planet outside the USA though...
I'll see your Constitution and raise you a Queen.
A decent point, but lots of renewable energy sources readily produce methane. Which can be easily stored, if you don't mind a heavy pressure tank. (Think propane tank. So it's not all *that* heavy, but it sure isn't light.)
I think we've pushed this "anyone can grow up to be president" thing too far.
"Your diesel runs significantly less than 1000 deg C. most run at ~550C or less."
For instance look at figures 5 and 6. http://www.engineering-4e.com/diesel.pdf
Maximum cycle temperatures for a diesel are shown as between 1500K and 2100K which is 1200C to 1800C
On a theoretic basis, that is what gives a diesel such a high thermal efficiency.
Methane-and-stuff. You need some rather bulky equipment to purify it for cells. It'd mean your remote country house would need someone to bring a tanker around from time to time, just like is the case with oil- or gas-heating already.
This could evolve to underwear that powers your phone!
Funnyhacks - Wierd, unusual, and fun hacks
2kW average may do the job for the most part... You can argue that the heating system, stove and hot water heater should run on gas... but in the South, we like our air conditioning. 2kW won't even kick over the compressor in my home's system. I recently did the calculation for what I need, in terms of a backup generator. It was on the order of 10-12 kW to handle the peak load (HVAC startup).
Yeah! Someone needs to invent Shipstones!
I didn't think that comment was particularly offtopic. I've been saying for years that storage and not generation, is a bigger problem.
Solar panels are getting pretty cheap - although it pisses me off that they keep pumping money into making them more efficient rather than making them cheaper. While I'd love to have super-efficient panels that mean I never have to plug in my phone or laptop again, I'd sooner have "normal" dirt cheap panels I can replace the tiles on my roof with.
I'm still waiting for my Sodium Sulfur Battery - 50kWh storage in a fridge sized unit with a 10 year life cycle @$4k...
Of course, once we've figured out how to store free power cheaply, it doesn't take a genius to figure out who's holding us back from that...
Gas powered heat pumps can be more than 100% efficient as well. The natural gas to runs an ICE that provides mechanical power for a compressor. You recover exhaust heat and your overall exhaust is actually colder than ambient. Current efficiency's range from about 120 to 150%. A small generator can be attached to the shaft as well and provide enough power for control and to possibly operate a blower. It is a neat system, but they are not catching on.
There's a fairly new commercial product called BlueGEN https://www.bluegen.net/ which connects to a domestic natural gas supply; I think they're marketed more toward light industrial use, but if the price comes down (currently ~ $45K Australian) it could be an excellent distributed electricity generation option.
For Natural Gas (@0degC)
Specific Heating = 47.7MJ/kg
gas density = 0.72 kg/m^3
cost ~= 0.25 $/m^3 (typical Ontario with distribution)
efficiency = 50%
= 4.77 kWh/m^3
= $0.052 / kWh
this would assume it could run on natural gas, but it needs pure methane. Even so, it ends up cheaper than grid electricity.
Who knew? Isn't methane regularly burned off at oil refineries? Never quite understood wasting it. Same could be said of dairy farms and cattle feed lots although it probably would cost a lot to harvest it out of the air.
Well, my grandfather had propane delivered that way, so I don't see why it couldn't be delivered that way today. And most of the "green bio-fuel generators" are designed to work in an industrial environment. It's not a replacement for the compost pile, but rather for the oil-well. (Admittedly, it doesn't do a good job of replacing the oil well, but it's not something that will soon run out, either. And it doesn't add to the carbon dioxide level the way burning oil does. And as oil gets more expensive, the alternatives all start looking better, even though none of them are quite a flexible, so you need to implement a large variety of methods.)
That said, I've got my doubts about this particular approach leading anywhere. But it's not my baby, so I don't need to care. Every approach seems unlikely when it first appears. Some of them start looking a lot better after they develop a bit. But if you want something for your rural homestead that doesn't require outside servicing, build your own windmill or water wheel. If you need to buy parts to build it, you aren't going to be independent when it breaks. Note that I didn't suggest something even as high-tech as a steam engine. Too many parts that YOU won't be able to replace. Or, you could admit that you don't want to be that independent, and accept buying deliveries of propane, and buy an occasional part for you water pump, etc.
I think we've pushed this "anyone can grow up to be president" thing too far.