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Panasonic ENE FARM Residential Fuel Cell

Panasonic ENE FARM Residential Fuel Cell

Most of the big players in the USA who were initially planning on providing fuel cells for residential homes have either gone out of business or shifted to selling products for Telecom backup.  It’s simply easier and more cost effective for them to sell thousands of units to a single customer who has established maintenance infrastructure than to sell a single unit to 1,000 individuals who may not be as rigorous on installation and maintenance.  This means that if you are a single home who wants to either go off-grid or partially off-grid with a fuel cell, you essentially have to build it yourself at the moment or we can assist you with putting together a one-off system.  Since there isn’t a commercially available option, custom systems can cost $35,000 – $100,000+.  The fuel cell industry changes so frequently, if there is a provider for residential fuel cells out there currently delivering actual products, please leave a comment and a link or email us.

By the way, we work primarily with PEM fuel cells so this article will mostly be addressing those.

 

Hydrogen Supply

First off, you will need a supply of Hydrogen to fuel your Fuel Cell.  Depending on your goal, you can get this in several different ways: delivered hydrogen (e.g. tube trailers, cylinders, etc), on-site generated (e.g. electrolyzer) or reformed.

Delivered – This is pretty straight forward.  You pay someone and they bring you Hydrogen, typically in either a tube trailer, 6-pack of gas cylinders, etc.  This would be common for emergency backup type of systems where the system isn’t consuming hydrogen continuously and is only used periodically or in emergencies.  This would not be uncommon for the Telecom backup systems since they typically are only turned on briefly once a month for testing and only need enough hydrogen on-site to run for several hours in case of loss of primary power.

On-site Generated – This would be the most renewable option and is typical for fully and partially off-grid applications.  In this case you would take power when it’s available and use it to generate hydrogen by electrolyzing (splitting) water.  This Hydrogen is then stored for periods when you do not have power available.  A common scenario might be if you have solar you may use excess solar power during the day to generate hydrogen, then when the sun goes down or on a cloudy day you can consume the hydrogen you generated previously to generate electricity in your fuel cell.

Reformed – This is a process for taking hydrocarbons (typically Natural Gas [NG], Propane, etc) and reforming it in a combustion chamber to produce hydrogen gas.  For use in a PEM fuel cell the hydrogen would need to be purified.

 

Hydrogen Storage

Once you have your hydrogen, you often will want to store it.  How much hydrogen you want to store will depend on how much power you need (and the hydrogen consumption rate at that power) and how long you need that power.  In the solar example above, if you assume that you will be generating excess electricity from solar for 8 hours a day and that you will consume 2 kW for the other 16 hrs you will need:

26 LPM Hydrogen (from the 2 kW FC Specifications) * 60 min/hr * 16 hrs/day = 24,960 L per day.

Assuming you will be consuming the full 2 kW the entire time.  If you operate at less than 2 kW you will obviously consume less fuel.

This is the equivalent to approximately (5) K sized bottles of Hydrogen.  Not unmanageable.

You can also store at much higher volumetric densities using metal hydrides.  These will be more expensive, but if space is a concern it may be worth it.

 

The Fuel Cell

horizon-fuel-cell-stack-home-residentialNow we get to the heart of the system, the fuel cell.  This is actually not that complicated either.  You can purchase a fuel cell stack that has basic system and controls and outputs a variable level DC that can then be converted to AC for your home (see next section).  Please note that these fuel cells will not operate below freezing.

We can spend a little more effort in this section speaking about how big of a fuel cell you need.  For homes, the rough approach is to take your monthly utility bill with your monthly energy usage in kWh and divide that number by the number of hours in a month.  For example, if you were billed for 909 kWh in a typical 30 day month (the US average, according to US Energy Information) that would be:

909 kWh / 30 days / 24 hrs/day = 1.26 kW

Note: this is the average power consumption of the home over the month and does not represent the amount of power your home draws at any given time.  For example, during periods when the air conditioner, heater, microwave, hair dryer, etc is operating you may consume significantly more than this.  When it shuts down you will consume much less.  If you are operating a grid-tie system, then you are probably good to size for the average consumption.  During periods of high demand you will use extra power from the grid while during lower usage time you could put power into the grid, giving you a net zero energy usage (how you’re billed/credited will vary with your local and state regulations).

If you are working to be completely off-grid with no connection at all, you will need to analyze your actual expected loads at any given time a little closer and be sure that your system can handle the larger sustained loads (e.g. while the AC/Heat is on) as well as any transient loads (e.g. the very short spike that occurs when motors or compressors first come on – this can often be taken up with a small battery bank).  One way to do this is to just make a list of all of your loads and start adding them up.  The more advanced method would be to use some of the home power monitoring products to get a map of your power usage over time.

 

Connecting to your Home

This can be a little more complicated.  If you are 100% off the grid and do not have any connection to the local power grid you can use a standard inverter.  If you are connected to the grid you will need to use a “grid tie” inverter.  This matches the AC output with the grid AC so that it is in-sync and doesn’t cause any damage to the equipment/grid/etc.  These are more expensive.

General Safety: Remember to take care in working with flammable gas of any kind.  While Hydrogen actually has many characteristics that make it safer than gasoline (e.g. it disperses more rapidly, has a narrower flammability limit, etc) it is still dangerous.  Especially since it is typically in compressed form and so exhibits all the safety concerns of any compressed gas.  Be sure to include hydrogen sensors in any enclosures which will trigger safe shut down and that everything is proper ventilated, etc.  As with any potentially dangerous chemical or device: If you don’t understand working with Hydrogen, don’t do it.

Comments

  1. Are any companies still producing a product for residential use?

  2. Any companies/contractors that install in Southern California? I got a hold of a 5kw fuel cell need to get storage and generator

  3. Are there any companies that do a home audit and install in Connecticut?
    How much would the cost be for an average home?
    Thanks

    • Hi Joe,

      Unfortunately, we do not do too much work in residential or large-scale fuel cell applications but we may have one thing that would fit your needs. For residential home fuel cell applications the closest available is currently priced at around $35,000. I have attached an image below with specifications for your reference. It is different in that it is designed as energy storage for renewables (PV/wind) and does not operate on natural gas.

      Residential Fuel Cell Application

      Other than this system, the ENE FARM (made by Panasonic) is not available in the USA at this time and I do not know if / when Panasonic would have plans for a USA version.

      Some specs of their Japan version are here: http://panasonic.co.jp/ap/FC/en_doc03_00.html

      I hope this helps!

  4. John Shwope says:

    We have a now non-operative hydrogen fuel cell system at our home. It was built by Clear Edge Power. It generated 5 kWh using natural gas. Unfornately the company went bankrupt, not because of this unit, but because they took over a company that built large industrial units, and was overcome by its debt. Where was the federal government, oh yes, balling out the already dead Solyndra. Mine was a “beta” model, that was being replaced with their new consumer unit when they declared BK. For 2 years, on the grid, the unit produced 3500 kWh/month, including maintenance downtime, which the new unit greatly reduced. The by product was heat, which through a heat exchanger and an auxiliary hot water storage tank, delivered 124+ degree hot water, or wherever I set it. When it hit temp, a valve turned and the heated h2o went to the pool. Actually to the spa, which because the main pool pump shut off at noon, reculated the hot water rather than dumped it into the pool. Every night at 6pm the water was 95 degrees. The gas to out hot water heater, including the pilot, was shut OFF. Subtract the gas saved in hot water production, from the gas used for the fuel cell, brought the gas cost of the cell to about $120/month. Not for the small electric user, but it saved me about $900/month, including the reimbursement from the electric company for all the time my meter ran backwards. It ran virtually silent rain or shine 24/day. It’s the size of a small refrigerator and still sits next to the garage. I just opened the panels/doors for the first time the other day and marveled at the hi tech gear inside. Pictures available upon request.

    • Hello John,

      That’s awesome to hear! It is always amazing to hear of residential fuel cell applications being used properly and efficiently such as yours. We would love to see some pictures! Would you mind emailing us at fuelcells@fuelcellsetc.com with the pictures?

      • John Shwope says:

        Thanks for the compliment. I was so efficient, that since we were redoing our pool equiment at the same time, I ordered an electric “heat pump” instead of a gas pool heater. Slower, but FREE, with the Fuel Cell. Not so much now. The CEP cabinet had the heat exchangers inside, as well as the exhaust out the top. When they shut it down waiting for the new unit to come out, they removed the fuel cell and another large area which I believe were the heat exchangers. Other than that it’s intact. They were paying my electric bill while I waited for the new unit, rather than keeping up the maintenance the “beta” unit required until the BK. Ill send the pictures to your website. You can post them here if you wish. I’d love to be able to use all this wiring and plumbing with a new fuel cell. I now have 2 hybrids to feed as well.

  5. I would like to get more information on cost. Lets assume I have a 5 kWp solar PV installed.

    How much would it cost me to get an electrolyzer, an hydrogen storage tank and a fuel cell to store my solar power and use it at a later stage?

    I am aware the cost component will depend on the size etc. Therefore, lets assume I would like to increase my self-consumption rate of solar power from 30 to 70 %. That means I would like to store approximately 10 kWh solar electricity per day.

    Finally, what is the approximate efficiency of converting solar power into hydrogen and then re-converting the hydrogen into electricity via the fuel cell?

    Rough estimations would be totally sufficient for my use. Thank you very much!

  6. John Shwope says:

    I’m not sure I understand your question, but as far a my fuel cell went, it used the natural gas from our local gas company line, which I believe is CH4, “lots of Hydrogen”, and separated out the “H” and ran this pure hydrogen through the fuel cell to covert to electricity which went into the line just like a solar hook up does, and ran at about 5kWh 24 hours/day. Sometimes the meter ran backwards, but gave us more than 100% of our needs. The “new” model that I was supposed to get also had the capability to run a certain number of select circuits in case of a power failure. Like certain lights and refrigeration etc. It never got here unfortunately. We did NOT store electricity for future use since it ran 24hr/day. It could be set up to do so however.

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