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Click on a frequently asked question below to jump to the answer.

1. What is a fuel cell? How does it work?
2. What are the advantages of the HomeGen 7000?
3. Can you explain further how the HomeGen 7000 helps the environment?
4. What are the components of the HomeGen 7000?
5. What size will the HomeGen 7000 be? How much power will it supply? What types of fuel will it use?
6. When will the HomeGen 7000 be available?
7. How will GE distribute the HomeGen 7000?
8. How do I find out what savings I might expect from using a HomeGen 7000 in my home?
9. Do I go completely off the power grid once the HomeGen 7000 is installed?
10. Will I have to change the wiring in my home with the installation of a HomeGen 7000?
11. How do I obtain a unit?
12. Will I be able to sell electricity from the HomeGen 7000 back to the grid?
13. Does the HomeGen 7000 need any upkeep?
14. What if my HomeGen 7000 experiences an "outage"?

15. Can the HomeGen 7000 operate off of biogas or waste gas?
16. Does the HomeGen 7000 pose any health hazards?
17. How safe is the unit?
18. Are fuel cells new technology?


1. What is a fuel cell? How does it work?
A PEM fuel cell operates like a battery in that it creates electricity through a reaction that combines the hydrogen in fuel (such as natural gas or propane) and oxygen from air to produce electricity. Fuel cells extract hydrogen ions from hydrocarbon fuels and combine them with oxygen to generate power. The output from the process includes electricity, water and heat.

Click here to link to our Product Description for more information.


2. What are the advantages of the HomeGen 7000?
Click here to link to our Benefits page for more information.

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3. Can you explain further how the HomeGen 7000 helps the environment?
Because of the fuel cell technology, widespread use of the HomeGen 7000 would reap dramatic environmental benefits for the following reasons.

Emissions Reductions
Traditional utility mixes produce significant emissions, inherent to combustion technologies, such as NOx, SOx, and particulate matter (PM). Studies have linked these emissions with acid rain, smog, and degradation of public health.

Fuel cell use will combat the environmental effects of combustion-based power generation by reducing emissions of particulate matter and other pollutants -- carbon monoxide, nitrous oxide or sulfur dioxide. Replacing existing combustion technology with new fuel cell technology would dramatically reduce air pollution, including those substances that cause acid rain. Fuel cell power systems can also help curtail growth in greenhouse gas emissions believed to lead to global warming.

Improved Efficiency
Traditional utility generation is about 30% efficient. Another 8% of that resulting electricity is lost to inefficiencies in the transmission and distribution. This results in overall efficiencies of less than 30%.

The HomeGen 7000 offers higher efficiencies of near 38%, requiring less fuel to produce an equal amount of electricity than traditional combustion technologies. This will extend the use of the earth's finite natural fuel resources. Eventually, the heat may be captured and reused for heating hot water or providing winter heat, thereby eliminating waste heat escape into the atmosphere. Heat recovery could increase the HomeGen efficiencies to as much as 75% or more.

Preservation of Habitats
The HomeGen 7000, like other distributed generation, eliminates the need for the transmission and distribution facilities such as substations, poles, and wires. All of these elements pose a burden on the land, habitats, and living creatures.

For more information on fuel cells and environmental issues, we recommend the following sites:

    National Renewable Energy Laboratory
    Natural Resources Defense Council
    Energy Efficiency/Renewable Energy Network
    Rocky Mountain Institute
    Solstice: Sustainable Energy and Development Online
    Northeast Sustainable Energy Association


4. What are the components of the HomeGen 7000?
Subsystems of a fuel cellThe HomeGen 7000 can be thought of as three major subsystems: 1) a fuel processor, 2) fuel cell stack and 3) power conditioner.

Fuel Processor
The fuel processor portion of the power system can be divided into two distinct operations: the fuel reformer and the carbon monoxide (CO) cleanup unit.

The fuel reformer processes a hydrocarbon fuel, such as natural gas, propane, methanol, or gasoline, into a hydrogen rich gas known as reformate. Typically, the CO content of the reformate after it leaves the reformer is very low (less than 2% or 20,000 parts per million (ppm) but still much higher than current PEM fuel cell tolerance levels of 50 ppm.

Since the reformate still has CO concentrations of several thousand ppm, current systems require a CO cleanup subsystem to reduce the CO content to less than 50 ppm. CO cleanup can be accomplished through two primary technological means: 1) physical separation, generally achieved through membrane separation or adsorption/desorption, or 2) selective CO reactions such as preferential oxidizers (PROX) or methanizers, meaning that the CO is reacted with another gas and converted into another compound such as carbon dioxide (CO2) or methane (CH4). The current state of technology seems to favor the selective CO reaction methods because of their potential low cost design concepts and near-term commercial viability.

Fuel cells extract hydrogen ions from hydrocarbon fuels and combine them with oxygen to generate power. How a fuel cell works The output from the process includes electricity, water and heat.

Fuel Cell Stack
The PEM fuel cell is comprised of a membrane electrode assembly (MEA) sandwiched between gas diffusion layers (GDL) and bipolar plates on each side. The reformate from the CO cleanup system feeds the fuel side (anode) of the fuel cell. The fuel flows through the flow field in the bipolar plate so that the fuel will be in contact with the entire surface area of the fuel cell anode. The hydrogen in the fuel passes through the GDL, which typically has three functions within a PEM fuel cell. The first is to diffuse the reactant gases across the surface of the membrane, second is to manage the water around the membrane and third is to provide a highly conductive path between the membrane and the bipolar plates. The MEA includes the polymer electrolyte membrane with catalysts covering both sides, and serves the function of ionizing the hydrogen, passing the hydrogen ions, and combining the ions with oxygen to form water. MEA catalysts are typically made of precious metals such as platinum. Recent breakthroughs have reduced the thickness of platinum coating required, hence reducing costs dramatically. The cost of platinum has fallen from $1200/ per kW in 1980 to $5 per kW today. Intrinsic to the materials used, low operating temperatures of 80C and less are possible. This lends the advantage of safely operating in small power applications. The cell is also able to sustain operation at very high current densities leading to a fast start capability and the ability to make a compact and lightweight cell. Additionally, the cell includes no corrosive fluid hazards.

Single Fuel Cell
Single Fuel Cell
Fuel Cell Stack
Fuel Cell Stack

Several fuel cells in series creates a fuel cell stack capable of producing many kW of power.

The fuel cell stack is comprised of numerous individual cells stacked together to provide the required power, e.g., HomeGen 7000 stacks have approximately 100 cells.

Power Conditioner
The power conditioner first converts the low voltage direct current (DC) produced by the PEM fuel cell to a high voltage DC. An inverter then transforms the high voltage DC to 120 or 240 volt alternating current (AC). Batteries are an integral part of the power conditioner unit. They assure that power surges, e.g. from air conditioner start-ups, can be handled. Batteries also meet any extended peak periods of demand which are higher than stack peak output. The technology to condition power is well established and has been used in thousands of photovoltaic, wind, and standby generator applications.

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5. What size will the HomeGen 7000 be? How much power will it supply? What types of fuel will it use?
The unit is expected to be about the size of a refrigerator when it is commercialized and will be designed with dimensions that allow it to fit through a standard doorway. Though it will require minimal space, customers will have the option of installing the unit inside or outside their home. Our first product, HomeGen 7000, will provide enough output -- 7kW -- to power an average sized home, along with meeting peak loading concerns. In the future we may manufacture a variety of models for different sized homes. The exact number will be determined during our pre-commercialization testing period.


6. When will the HomeGen 7000 be available?
The HomeGen 7000 product will be available in the US markets in the year 2001 and Western Europe in late 2001. Residential HomeGen 7000 trials are expected to start in 2000.

Please fill out our survey to be added to our list of future interested customers and to help us understand the custom needs of your home.

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7. How will GE distribute the HomeGen 7000?
GE will not be selling directly to end-consumers. GE will select qualified energy industry companies with the know-how, service-support, and sales support to reach our markets.

The model of selling the HomeGen 7000 may vary by distribution partner. Some may own the units and sell the electricity output. Others may sell the unit outright to the residential customer. Others yet may own the units and dispatch the electricity at their own discretion onto the grid where and when it is needed.

Regardless of the distribution model, it may be possible for HomeGen customers in many regions of the country to realize savings of 20% or more over their current rates.


8. How do I find out what savings I might expect from using a HomeGen 7000 in my home?
Your electric bill savings depend on the following: your electric utility, your gas utility, and your electric usage.

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9. Do I go completely off the power grid once the HomeGen 7000 is installed?
Not necessarily. While you may have the choice to do so, you may opt to stay connected as a source of back-up power. Representatives are working closely with government officials to make this a low cost option.


10. Will I have to change the wiring in my home with the installation of a fuel cell?
No. A fuel cell system will merely replace the utility feeder to your breaker box. All the wiring within your home will remain the same.

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11. How do I obtain a unit?
Once commercial product is available in 2001, GE will be distributing the HomeGen 7000 through regional resellers. Keep posted to the site to find out which resellers will serve your region.

Please fill out our survey to be added to our list of future interested customers and to help us understand the custom needs of your home.


12. Will I be able to sell electricity from the HomeGen 7000 back to the grid?
Depending on the state, legislation exists either allowing or not allowing residential customers to sell power back. These laws are usually commonly referred to as "net-metering" laws. In some net-metering states, the utility will permit the meter to net back to zero - meaning essentially that the utility will purchase back as much power as the residential customers consume from the grid in a given time period. And in others, the utility may purchase any surplus power from the residential customer, called an "avoided cost," or the cost to otherwise purchase bulk power. In most cases this "avoided cost" is only a fraction of the retail cost. In most states, these laws are subject to change given the onset of deregulation and the introduction of choice and flexibility to residential customers in their power production and purchases.

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13. Does the HomeGen 7000 need any upkeep?
The GE HomeGen 7000 has a long life and needs little maintenance. The system does require a simple annual check-up by an authorized service technician and component replacements every four to six years. This maintenance ensures reliability and power availability. You may opt for a service contract through GE resellers to avoid having to administer this maintenance yourself.

The qualified GE reseller in your region will have a service network with 24-hour on-call service support to immediately respond to the repair of your HomeGen 7000.


14. What if my HomeGen 7000 experiences an "outage"?
The HomeGen 7000 also has a telecommunication control system that links your system to the GE Service Center. The online service experts can diagnose the problem and take action by fixing it immediately or sending a technician to your home even before you detect a problem.

For those customers desiring full insurance, there will be long-term service agreements available with your HomeGen 7000. The agreement puts the responsibility of your electric service in the hands of an authorized service provider.

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15. Can the HomeGen 7000 operate off of biogas or waste gas?
Not at this time. The fuel cell stack within the HomeGen 7000 can run off of any hydrogen rich fuel (reformed methane (natural gas), ethanol, or gasoline, etc.). Methane based waste fuels contain more impurities and require more sophisticated clean-up processes. But they hold promise as future fuels for the GE fuel cell products.


16. Does the HomeGen 7000 pose any health hazards?
Exposure to harmful emissions?
The main by-products from the HomeGen 7000 are carbon dioxide, nitrogen, and water. An exhaust line will vent these outside the home. None of these are health hazards at the level produced. The carbon dioxide released per kWh is less than the cleanest, state-of-the-art natural gas turbine plants available to traditional power utilities.

Exposure to chemicals?
The electrochemical reaction occurring in the fuel cells within the HomeGen 7000 is no different in nature than those in batteries, which we carry with us in our lap-top computers, telephones, portable radios, and cars every day. Yet fuel cells employ none of the hazardous substances or acids that some batteries may. The reaction is H2 + O2 = H2O.

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17. How safe is the unit?
The HomeGen 7000 will be as safe as other common natural gas appliances commonly found in homes - furnaces, clothing dryers, hot water heaters, stoves, and ovens.


18. Are fuel cells a new technology?
Fuel cells have actually been on the scene for nearly 150 years. Invented by Sir William Robert Grove in 1839, it wasn't named for nearly 50 years when Mond and Langer dubbed this new source of power a "fuel cell." In 1932 Francis Bacon greatly advanced the concept, and by the 1960s, it was being used in space exploration, helping power Gemini and Apollo missions. Then years later the oil embargo brought renewed interest in fuel cells. Recent government regulations--the Clean Air Act of June 1997 reinforced the US commitment to greenhouse gas reduction with target dates of October 1997 and January 1998--have furthered growing utility deregulation and augmented consumer demand for cleaner energy sources. Now at the close of the century, there is a major push for fuel cell commercialization, with potential applications ranging from residential to automotive to portable power.

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