Plugging in to opportunity

The commercialization of fuel cell technology has been a long time coming. John Mousaw of Plug Power, USA, explains how technical advances, spurred on by deregulation, are at the point of bringing the technology to your front door.

Increasing industrialization and energy deregulation are having a profound effect on power generation markets throughout the world. These changes are pushing diverse technologies for distributed power, grid augmentation, cogeneration and emergency power schemes to the forefront.

Electric utilities looking to survive in the flourishing competitive environment are seeking new products and services that will help them meet these changing needs – particularly in supplying the consumer segment. One solution is clean, efficient and reliable fuel cells – an economical way for electric utilities to expand their product portfolios for both residential and small business customers.

As one of the leaders in the race to commercialize fuel cell technology, Albany, NY-based Plug Power has been focusing its efforts on small-scale stationary systems. These “energy machines” which are being designed to be about the size of a dishwasher, can supply a typical-sized residence, or small business, with its complete electricity requirements.

Almost one year ago, Plug Power unveiled a prototype of this system at what became the world`s first fuel cell powered home. In early 1999 it finalized a joint venture world-wide distribution deal with GE Power Systems and recently completed the successful demonstration of a natural gas-based PEM fuel cell system.

The joint venture company – GE Fuel Cell Systems will distribute fuel cells worldwide, and there are many opportunities out there. GE Power Systems owns 75 per cent and Plug Power owns 25 per cent of the new joint venture company. As part of the joint venture agreement, Plug Power will work closely with GE`s Corporate Research & Development Centre for product development and manufacturing support.

Plug Power of Latham, NY, was originally formed as a joint venture between DTE Energy Company, a diversified energy company involved in the management of energy-related businesses, and Mechanical Technology Inc., an early developer of fuel cell technologies. It was formed to develop and manufacture fuel cells for power generation in residential and automotive applications. Formed in June 1997, Plug Power has grown from 22 to over 200 employees, making it the largest PEM fuel cell company in the USA.

GE Fuel Cell Systems will market, sell, install and service Plug Power-designed and -manufactured fuel cells, up to 35 kW, for residential and small business power applications on a worldwide basis.

Breakthrough technology

Originally discovered in 1839, fuel cell technology has been used by NASA in space applications since the early 1960s. Technical breakthroughs along with reductions in the cost of materials have made this proven technology available to a virtually limitless range of energy applications. Once commercialized, fuel cell power systems will revolutionize the concept of a utility distribution system.

Proton exchange membrane (PEM) fuel cells are generally considered the most promising fuel cell technology, and are being developed by Plug Power for use in the domestic and commercial market. PEM cells operate at relatively low temperatures (about 95 degreesC), have high power density, and can vary their output quickly to meet shifts in power demand. According to the US Department of Energy, “They are the primary candidates for light-duty vehicles, (where quick start up is required) for buildings, and potentially for much smaller applications such as replacements for rechargeable batteries in video cameras.”

PEM fuel cells are highly sensitive to fuel inputs, and therefore have higher fuel reformation costs. However, because PEM fuel cells require almost pure hydrogen fuel, they produce virtually no emissions – just one of their main advantages.

The development of fuel cell technology has been spurred on by knowledge of the many benefits that will result from its commercialization. Fuel cells offer increased efficiency. They require less fuel than traditional combustion to produce an equal amount of electricity. Also, since a significant percentage of the heat produced by fuel cells can be captured and reused – rather than being released into the air or water – this can more than double their efficiency. With on-site power generated by fuel cells, energy losses from transmission and distribution are eliminated as well.

On-site power with fuel cells is also much more reliable, benefiting individuals and businesses that rely on uninterrupted power. Because there are no connections to outside lines or wires, fuel cells are not affected by weather-related power outages. They contain no moving parts, rendering the system both easy to maintain and relatively noiseless. Fuel cells can significantly contribute to the abatement of the environmental effects of power generation by reducing emissions of particulate matter and other pollutants – such as carbon monoxide, nitrous oxide or sulphur dioxide – to near zero.

Most significant from a consumer standpoint, fuel cells cost less to operate. Many residential power customers will save up to 20 per cent off their electric bills upon the system`s introduction.

Fuel cells also provide strategic benefits for electric utilities, especially in distributed generation applications:

• Defer expensive transmission and distribution (T&D) system expansions

• Increase the life of substations

• Decrease maintenance costs by reducing loads on heavily used distribution assets

• Improve distribution system reliability

• Provide high quality to end-users.

A market reality

Globally, there are more than 1.2 billion households that may be without electricity. To complicate matters, many countries do not have the means to secure the financing necessary to build large, central power projects and accompanying transmission and distribution networks to serve a broad customer base. Other regions have electricity that is unreliable, too costly or generated by high emission, fossil fuel power plants.

Fuel cells are ideal for developing areas such as India, southeast Asia and Latin America to help eliminate the costs and inconvenience associated with power outages. They are also suitable for remote regions that are far-removed from utility grids. In more developed countries throughout Europe and North America, fuel cells remain a cost-effective option for distributed generation and emergency or back-up power configurations as well as uninterrupted power supplies.

Field-testing will begin in late 1999 and will continue through 2000. Plug Power will produce multiple “alpha” units in 1999 and place them with various utilities located throughout the United States – including Detroit Edison, New Jersey Resources, and Long Island Power Authority – for testing and further development.

Beginning in 2000, GE Fuel Cell Systems “beta” testing will expand to 500 units and involve actual homeowners. The sites will be selected based on criteria such as: size and location of home, accessibility to the proper fuel input and load profiles. The company expects to offer commercial units beginning in January 2001.

GE Fuel Cell Systems is beginning to partner with carefully selected resellers that will market the systems to end-users within defined territories, and recently closed a deal with New Jersey Resources. Resellers will likely include companies where GE Power Systems already has strong relationships, such as electric uilities, natural gas and propane distribution companies, electric service companies and gas and power marketers. GE Fuel Cell Systems also expects to partner a select group of service providers in order to offer resellers and end-users a global network of high-quality, cost-effective installation and maintenance support.

Due to technical and production advances by Plug Power, GE Fuel Cell Systems expects to offer residential-sized systems in 2001 for $7500 to $10 000. Moreover, prices are expected to fall dramatically over time as production volumes increase and manufacturing efficiencies are achieved. In mass production, a residential fuel cell system is expected to retail for approximately $3500. At that price, fuel cells can generate electricity at ٛ-10/kW-hour, depending on usage and the fuel costs in a given market.

The initial commercial units will operate on natural gas, propane, or methanol and are expected to achieve 40 per cent electrical efficiency. When excess heat generated by the fuel cell is captured and used for hot water or heating, overall efficiency can exceed 70 per cent. Another strong advantage, fuel cell systems can be sized to match consumers` specific energy requirements and in many regions, will provide an attractive alternative to grid-supplied power.

Plug Power is also pursuing automotive fuel cell development in tandem with its residential programme, and the technology employed in both applications overlaps to a great extent.

However, because automotive fuel cells have stricter parameters – with regard to size, weight, shock absorption, and temperature sensitivity – residential systems offer the potential for commercialization within a much shorter time frame. The company intends to leverage both the market experience and economies of scale gained from mass market production of residential fuel cells, thus facilitating its entry into a substantially more competitive automotive arena.

New advances

Plug Power recently announced that it has completed the successful demonstration of a natural gas-based PEM fuel cell system. The residential-sized system – that includes a fuel cell stack, power conditioner and a Johnson Matthey fuel processor – produced in excess of 4 kW of electricity at the company`s upstate NY development facility. Johnson Matthey of the UK is a world leader in advanced materials technology.

This operation of a complete system on natural gas is an important step toward bringing Plug Power`s residential units to market in 2001. The natural gas breakthrough means that more than 70 million homes that already use natural gas for heating and cooking in the USA alone will eventually be able to use natural gas-powered fuel cells to meet all their energy needs.

The natural gas system uses the same design as Plug Power`s 7 kW fuel cell prototype – which has operated since June of 1998 on hydrogen. Plug Power integrated a Johnson Matthey HotSpot natural gas fuel processor into its fuel cell system. The AC electricity generated from the fuel cell was used to power part of the company`s laboratory facility. Plug Power also has operated a methanol-based fuel cell power generation system.

Electric utilities can now add efficient and compact fuel cells to their product portfolios to meet the changing power generation needs of customers. Meanwhile, consumers will be able to use low-cost fuels like natural gas to generate low cost electricity.

What is a fuel cell?

A fuel cell is an on-site power generation device that produces electricity through an electrochemical, rather than combustion reaction. This process converts hydrogen extracted from a fuel (such as natural gas, propane, methanol or gasoline) and an oxidant (such as air or oxygen) into useable energy.

Fuel cell construction generally consists of a fuel electrode (anode) and an oxidant electrode (cathode) separated by an ion-conducting electrolyte. When a hydrocarbon fuel is introduced into the system, the catalyst surface of the electrolyte splits hydrogen gas molecules into protons and electrons. The protons pass through the electrolyte and react with oxygen to form water. The electrons, which cannot pass through the electrolyte, must travel around it, thus creating the source of DC electricity.

Other products of this reaction include heat as well as emissions typical of those generated by hydrocarbon fuel processing; however, these levels of emissions are significantly lower than those from even the cleanest fuel combustion processes.

In addition to PEM fuel cells, there are three major fuel cell technologies:

• Phosphoric Acid (PA): These fuel cells do not have to be reduced to pure hydrogen because they can tolerate exposure to carbon dioxide and small amounts of carbon monoxide. Because of these decreased fuel processing requirements, PA fuel cells are the most commercially available type; they are currently being used in larger facilities such as schools, hospitals, office buildings, hotels and utility power plants. PA fuel cells generate electricity at more than 40 per cent efficiency – and nearly 85 per cent of the steam produced is used for cogeneration. Operating temperatures are in the 205 degrees C range.

• Molten Carbonate (MC): MC fuel cells take methane (the main ingredient in natural gas) and combine it with steam to form gas within the fuel cell that is rich in hydrogen, thus the need for extensive fuel reformation outside of the stack is reduced. This enables the entire MC fuel cell power plant to have lower capital costs per kilowatt, and a higher power density per square foot than a PA fuel cell power plant. Electrical efficiencies are estimated between 50 and 57 per cent. Operating temperature is about 650 degrees C.

• Solid Oxide (SO): SO fuel cells have a greater level of fuel flexibility than MC fuel cells and are a promising technology for high power applications such as industrial and large-scale central electricity generating stations. A solid oxide system usually uses a hard ceramic material instead of a liquid electrolyte, allowing operating temperatures to reach 980 degrees C. The stability and high temperature operation of SO fuel cells eliminate the need for a fuel reformer. This feature allows SO fuel cells to be used in conjunction with combined cycle generators, yielding an overall efficiency of up to 65 per cent. In simple cycle operation, SO fuel cells have electrical efficiencies of 50 to 55 per cent.