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Bloom Unveils Its Game Changing Energy Box

mashable.com

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Re: Bloom Unveils Its Game Changing Energy Box

#31

Post by pingswept »

beambot wrote: post #15
mbreese wrote: post #11

Earlier quoted context omitted.

You put in a hydrogen source... in this case, likely natural gas. It combines with oxygen from the air in a process that yields electricity, water, and a small amount of CO2. The key benefit is that the fuel isn't burned. It's converted chemically, so it is a very efficient process. They have a good flash video explaining it here: http://bloomenergy.com/products/solid-oxide-fuel-cell-animat...

Any idea about the relative efficiencies between this chemical reaction versus a thermodynamic process (say, Sterling Engine)?

I don't think there's a clear winner yet. The devil is in the details, as they say. A good Stirling engine will beat a lousy fuel cell, and a good fuel cell will beat a lousy Stirling engine. Both are in the range of 20-50% when implemented well, but they both have lots of problems.

Fuel cells, for example, typically have a membrane at their core; that membrane tends to get clogged with crud. Stirling engines, on the other hand, are generally heavy (and thus expensive) and need to use exotic materials to handle high temperatures, which they need to operate efficiently.

Re: Bloom Unveils Its Game Changing Energy Box

#32

Post by bbot »

ashishbharthi wrote: post #26

As they mentioned it can work on variety of fuel sources, they can probably create Gasoline -> Fuel Cell -> Electricity -> Motor type powertrain and create very efficient cars like 100mi/1gallon or something.

Doubtful.

Solid oxide fuel cells are very efficient, but have lousy power density. A big cabinet full of Bloom fuel cells does 25 kilowatts. That's a lot of electricity, but it's only 33 horsepower. You would need two cabinets and a bank of capacitors, for lousy performance. Then you would need a tank of compressed natural gas, which also doesn't have awesome power density numbers, after you spend the power to compress it.

And, of course, solid oxide fuel cells aren't a turn-the-key-and-go kind of power source. They run at 1000C, and take an hour to get that warm, all while burning fuel.

More general concerns:

It's supposed to be multi-fuel, and is designed for third world use. But solid oxide fuel cells are notorious for having problems with catalyst poisoning. How have they solved that?

They mention that it's reversible, in that it can take air and electricity, and produce fuel. This is troubling, in that it is utter bullshit. No fuel cell can do this.

And of course, how is this green? It burns natural gas! It may be greener than a gas turbine power plant, but it still produces carbon dioxide.

Re: Bloom Unveils Its Game Changing Energy Box

#33

Post by teilo »

andrewcooke wrote: post #18
teilo wrote: post #4

Earlier quoted context omitted.

I believe the idea here is not that a single 1KW stack would be used to power a home, but that several homes would run off of a single 25KW module, so that you only need to accomodate their collective peak requirements

if you don't all get up and shower at the same time...

Let's consider this system in the context of the USA, where we have massive amounts of natural gas, but no efficient way to turn it into electricity. Existing turbine systems waste gas two ways: The inefficiency of combustion turbines, and transmission loss. Now, if we were to bolster our existing natural gas transmission infrastructure in order to support fuel cell technologies, we can presume that heating will continue to be provided by combustion heat exchange systems such as gas furnaces and water heaters.

Additionally, there are other ways we can generate fuel which can equally be used in combustion heat exchange and fuel cells. Chief among them is our garbage, much of which can be transformed into raw materials for methane production. Yeah, I know, the AGW folks will be crying foul on this one. I'm going to ignore them for the sake of this argument.

Now, even if you do not eliminate entirely the heavily centralized form of electricity production which we use now, you have dramatically reduced the load on the system as a whole by localizing power production in small modules everywhere. The result: say goodbye to rolling blackouts and cascading grid failures.

Re: Bloom Unveils Its Game Changing Energy Box

#34

Post by hendler »

Fuel Cells and Proton Exchange Membranes often use Platinum or Palladium as a catalyst - which is very expensive. Bloom's box uses something cheaper. The science/tech is used in a lot of places you might not expect, like submarines too. It can be the most efficient way to generate and process hydrogen as well. For example, if you put enough solar panels/wind turbines to power the United States - you would invest so much in power lines, and so much would be lost in transmission, that it's not economic. Fuel cells can generate hydrogen from water at the point of generation - I believe more efficiently than electrolysis. Then the hydrogen could be transported similarly to CNG. Then Hydrogen can be "burned" or run the other direction through the Fuel Cell.

The politics and economics are becoming more favorable. Glad to see coverage on Mashable.

Re: Bloom Unveils Its Game Changing Energy Box

#35

Post by bbot »

DannoHung wrote: post #23

The most interesting claim is that it's a reversible reaction. This explains the "it runs on solar" comment in that it can be used in place of batteries or a flywheel to store energy by turning the excess load back into fuel during peak generation from solar/wind and then expend it later.

The claim is "interesting " insofar as it is astoundingly unlikely, and almost certainly untrue.

The chemistry of solid oxide fuel cells are well understood. It only works one way. They don't produce hydrogen when you feed them voltage. It's like spinning the flywheel on a car engine backwards, and expecting gasoline to pour back into the fuel tank.

Re: Bloom Unveils Its Game Changing Energy Box

#37

Post by blhack »

dantheman wrote: post #36

Has anyone seen anything about costs? That actually lists dollar amounts? I know this isn't vaporware (it's running at a few companies), but I until we know how much it costs it doesn't really matter.

$800,000 per unit.

They hope to get it to ~$3000 in the next 5 years.

Re: Bloom Unveils Its Game Changing Energy Box

#38

Post by dantheman »

blhack wrote: post #37
dantheman wrote: post #36

Has anyone seen anything about costs? That actually lists dollar amounts? I know this isn't vaporware (it's running at a few companies), but I until we know how much it costs it doesn't really matter.

$800,000 per unit. They hope to get it to ~$3000 in the next 5 years.

Excellent -- ~3k is a price that makes me happy, 800k not so much. Let's hope as they move out prototyping to the assembly line they're able to achieve the economies of scale they're looking for.

Re: Bloom Unveils Its Game Changing Energy Box

#39

Post by clistctrl »

blhack wrote: post #37
dantheman wrote: post #36

Has anyone seen anything about costs? That actually lists dollar amounts? I know this isn't vaporware (it's running at a few companies), but I until we know how much it costs it doesn't really matter.

$800,000 per unit. They hope to get it to ~$3000 in the next 5 years.

haha, sounded like 800k was the price for the huge box (the kind ebay is running) and $3000 is the price of one big enough to run your home.

Re: Bloom Unveils Its Game Changing Energy Box

#40

Post by jws »

Grinding some numbers:

The data sheet says 661000 btu/hr of fuel to run at 100kw. 100kwh is 341,230 btu, so it looks like about 50% efficiency from shipped hyrdocarbon source to electricity on site. Very good.

On the american house using 1kw, that is obviously not a peak. At 8 cents/kwh, a 1kw average use house has a $57/mo electric bill. Looking at my bills I can only presume they counted a lot of small apartments and homeless people in cardboard boxes in the average.

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