Residential Fuel Cells - Natural Gas

ClearEdge Fuel Cell

ClearEdge Fuel Cell

We've covered the common types of alternative energy for your home - Solar PV, Solar Thermal, Small Wind, even Biomass - but until now we haven't even had a category for the residential fuel cell, much less a natural gas fuel cell.  The main reason for this is that up until now, there haven't been any options for residential customers who want to use a fuel cell to power their home!  Reinforcing that point is that a Google search for "natural gas fuel cells" turns up this very informative paper from the Department on Energy titled "Natural Gas Fuel Cells: Technology for improving energy efficiency while reducing environmental emissions"...the catch: it was written in 1995!

Thanks to several new companies arriving on the market this technology is getting a 21st century makeover.

The excellent blog Earth2Tech, which focuses on clean energy and smart grid technology companies, recently had two great entries on companies targeting residential Fuel Cells: Bloom Energy and ClearEdge Power.

The fuel cells you are used to hearing about in cars use pure hydrogen as the primary fuel, but both of these companies are using natural gas to power their fuel cell.  Why natural gas?  Because many consumers already have natural gas coming into their home (to cook with, heat their water, heat their air).  Natural gas is primarily made up of Methane, whose molecule is CH4 (1 Carbon atom and 4 Hydrogen atoms).  It is the best choice to use in residential fuel cells because it is usually easier to strip out the one carbon atom and be left with the hydrogen, than it is to find a hydrogen filling station (although that may be changing).   The fuel cell stack (see picture at top of article for a schematic of ClearEdge's fuel cell) runs off the pure hydrogen after the natural gas that comes into the unit is reformed (the carbon atom stripped away).

Bloom Energy

This company has massive funding from Kleiner Perkins Caufield & Byers  (which invests in several Green Tech ventures and Al Gore works with them) and has been generating a lot of buzz. This NY Times article on green capitalism has a great synopsis of how a Bloom Energy residential unit is performing in a trial at the University of Tennessee :

Over the past two and a half years, engineers at the University of Tennessee in Chattanooga have been testing a five-kilowatt Bloom box, which looks like a squat refrigerator and produces about as much electricity as a typical home requires. And at this point there seems little doubt that the idea K. R. Sridhar pitched to Kleiner in 2001 has become a high-functioning machine. “We installed one of his first units here to assess its durability and performance, to see if it matched the claims,” Henry McDonald, a professor at Tennessee who is overseeing the Bloom box, says. McDonald ran the box nonstop on natural gas for 6,000 hours, and its performance beat expectations. In everyday terms, the box was twice as efficient as a boiler burning natural gas, and its carbon emissions were 60 percent lower.

Until Bloom Energy comes out with more news about what they are doing (or actually reveals anything) then it's tough to speculate much more.

ClearEdge Power

Unlike Bloom Energy, ClearEdge actually has a picture of their product!  They have a nice, concise description of how their fuel cell works:

The Fuel Processor converts natural gas into ultra-clean hydrogen through a catalytic process, as opposed to burning the natural gas, which dramatically reduces pollutants. The hydrogen is processed through a Fuel Cell Stack, creating direct current (DC) power and heat. The Power Conditioning Unit converts the DC electricity into alternating current (AC), which then ties directly to the main electrical panel, providing steady continuous power for your electricity needs. The heat produced by the fuel cell is moved to the building through a heat exchanger supplying a continuous source of heating for hot water or space heating.

So this unit will create electricity AND heat for your home, making it that much more efficient.

In their FAQ section under the "How much does the CleanEdge5 cost" they say:

The list price for the ClearEdge5 is actually less expensive than equivalent residential solar PV systems, based on production. A major advantage over solar, the ClearEdge5 generates eleven times more energy than the same size solar installation. For the same capital investment, the ClearEdge5 gives you 90 MWh of annual combined electricity and heat, compared to approximately 8MWh generated by a 5kW solar system. Operating costs for the CE5 are as low as 6.0¢ per kWh based on $1.20 per therm for natural gas, assuming full electrical and heat utilization.

But I must point out two key points:

  1. It is a little unfair to compare a system (the fuel cell)  that - while efficient - still relies on fossil fuel as it's source of power to a system that (solar) only relies on sunshine.  I guess it is fair if CleanEdge is only assuming that solar buyers are only buying a solar system for the long-term financial payback over the utility grid, but this usually isn't the case.  While financial aspects usually make or break a decision to go solar PV, for the most part people install solar because the energy is completely renewable and only reliant on a free source of power - the sun.  But I understand that if buyers only want to buy a system that will save them money over the very long term, then yes, CleanEdge has an advantage over solar.
  2. Potential buyers, make sure you are aware that while the annual energy output of this fuel cell is more than a 5 kW solar system, a solar system has negligible operating costs!  With the fuel cell, you still have to pay for the system AND the natural gas it uses.  With a solar/wind system, you just pay for the system, and the fuel is free!

With that said, I am still a fan of the residential natural gas fuel cell.  If you have access to natural gas and you do need electricity and heat in your home (just about everyone), then I think this is a great technology. Improving the picture for residential fuel cells is that there is a Federal Tax incentive for them.  From the ClearEdge Rebates and Incentives page:

A federal fuel cell tax credit, an extension of the Investment Tax Credit (ITC), adds additional savings. A tax credit is different from a tax deduction, which subtracts money from gross income before tax liability is calculated. The ITC actually entitles the taxpayer to subtract the amount of the credit—dollar-for-dollar—from total federal tax liability.

For Home Owners, the fuel cell extension of the ITC will credit 30% of the cost of the unit, up to $1,000 per kW. When a ClearEdge5 is installed at a home, it qualifies for a $5000 total credit.

I would love to see some long-term payback studies! I still have some technical questions about these devices and I'd like to see a line diagram showing how one of these units connects to the home's electrical panel and how the heat is transferred to the hot water heater/furnace, but I'm sure more information will become available as they gain in popularity.  It is important to point out that these units are meant to supplement grid power, not replace it.

I look forward to seeing more from this section of alternative energy (though I can't call it renewable energy since it relies on fossil fuel, but it is energy).  I'm a fan of all technologies that make us more efficient in our daily lives and result in us using less coal to power our national grid.

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I will believe the NG FC is for real when I see a website featuring them and a "shopping cart" with the "buy now" icon and a price and the process continues with the credicard and shiopping address. but right now I dont see that so I am not convinced that they are not out of the R&D phase yet.
Does anybody have any new information on fuel cells? I just bought a house with a NG line on the property and have free usage of the gas. ClearEdge told me that they are only servicing California right now and BloomEnergy has not returned my email, although their website does not have any residential information on it.
ckmapawatt's picture
I believe they are the only two. make sure you are using the NG to heat your home, cook with, heat your water, etc. how do you have it for free?
Now here is the dilemma H2O has two strongly bonded molecules of Hydrogen. Methane has 4 and there are more bonds with other gases. So extracting from natural gas seems like the only alternative that gains enough energy back from the extraction of Hydrogen for the fuel cell. Well some genius chemist at MIT thought lets mimic a leaf and get H from H2O anyway because H2O is essentially free. Well they did it and made a substance that not only extracts H from H2O it regenerates its structure. A lecture if you will . It is also 10 times more efficient than a photosynthesis. So there is your free fuel that you need to complete the puzzle.
I have one of the CE5 units installed at my house. Runs well. Company support excellent payback 3.5 years. Can be used as backup generator also which is a nice feature. Simple install. I highly encourage anyone looking at shaving costs from pge to look at it.
ckmapawatt's picture
Keep in mind you are using natural gas as the fuel source...not electricity. That means that instead of a power plant using natural gas to convert it to electricity and wasting any heat that is generated, then sending that electricity through transformers and over electricity lines, you can generate it right where you need it and capture the waste heat to boot!
Why not incorporate solar cells to separate hydrogen from H2O. That would be the best of both worlds.
What reason would you have to spend energy separating Hydrogen from water? You won't get 100% of that energy back in a usable form. Simply put, you will consume more electricity separating the hydrogen from water than you will get back by passing the hydrogen through a fuel cell. (Read water fuel cell on Wikipedia if you want a detailed explanation) The only possible reason I could think of for doing this would be to use that hydrogen to store your generated energy, rather like a big gassy battery. Unless you're going to secure a massive hydrogen tank, you would be better off with a real battery anyway. I must ask, were you trolling? If so, I tip my hat to you. Cheers, @mostlegendary
Question about Solar...I assume that farries don't make solar pannels. There is a considerable amount of fossil fuels spent to manufacture them. The process used to manufacture the fuel cell technology is negligible in comparison. A 5kW solar array produces 8kWh anualy where a ClearEdge unit can support 90,000kWh per year. The fuel cell technology can sit next to your air conditioner unit and blend in with your house...a solar array is an eye sore and can't be hidden.
ckmapawatt's picture
Green, I think your data is WAAAAY off. a 5kW array is going to produce way more than 8kWh annualy. There's one important fact you left out: Solar is taking energy from the sun (which is free to use) but the ClearEdge (which I still think is an awesome product) is going to be using a fossil fuel (although a clean one) that you will be paying for.


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