Fuel Cell Efficiency

Stationary Power

Replacement of conventional electric generating capacity with fuel cells would result in significant energy savings, ranging from 880 Btu/kWh for marginal generation to 4,171 Btu/kWh for average fossil fuel generation. Possible efficiency gains associated with replacement of oil, coal and natural gas-fired generation would be as follows:

Potential Efficiency Gains Associated with Replacement of Existing Fossil Fuel Generation (Btu/kWh)

Potential Energy Savings from Replacement of Oil-Fired Generation

Potential Energy Savings from Replacement of Coal-Fired Generation

Potential Energy Savings from Replacement of Natural Gas-Fired Generation

Potential Average Energy Savings Resulting from Replacement of Marginal Generating Capacity

Potential Average Energy Savings from Replacement of Conventional Fossil Fuel Generation

4,609

4,288

3,976

880

4,171

 

This means that for each megawatt of existing conventional fossil fuel generation replaced with capacity from a fuel cell almost 35 billion Btu to over 40 billion Btu of energy, the equivalent of as much as 290,000 gallons of No. 2 fuel oil, would be saved annually. At 40 MW, the possible annual energy savings would be almost 1.6 trillion Btu, which is equivalent to nearly 12 million gallons of No. 2 fuel oil. With a CHP application and assuming additional increased efficiency from reduced transmission line losses, these savings could be doubled.

Potential Annual Energy Saving Equivalents for Each Megawatt of Generation Replaced with Capacity from a Fuel Cell

1 MW Btu and Oil Equivalent Energy Savings

1 MW

35 – 40 Billion Btu

1 MW No 2 Oil Equivalent

250,000- 290,000 Gallons

40 MW Btu and Oil Equivalent Energy Savings

40 MW

1.4 – 1.6 Trillion Btu

40 MW No. 2 Oil Equivalent

10 – 12 Million Gallons

Transportation

The amount of energy savings using fuel cells for transportation applications range from 2,407.40 Btu/mile for passenger cars to 16,264.20 Btu/mile for transit buses. The gallon per mile equivalent for a passenger car is 0.019 gal/mile and 0.12 gal/mile for a transit bus. It is important to note that although these numbers seem small, measurement is made in gallons/mile, not miles per gallon. The mile/gallon equivalent of 2,407.40 Btu/mile, which is the energy saved for passenger cars, is approximately 52 mpg. The first table below shows the potential equivalent energy savings using fuel cells for transportation applications compared to conventional fuels and technologies. The next table shows average miles per gallon estimates for conventional and fuel cell vehicles.

Energy Savings from Replacement of Conventionally-Powered Vehicles with Hydrogen-Fueled Fuel Cell Vehicles (Btu/mile)

Replacement of Gasoline Powered Passenger Cars

Replacement of Gasoline Powered Light Trucks

Replacement of Conventional Diesel Transit Buses

2,407.40

4,505.10

16,264.20

gal/mile equivalent energy savings

0.019

0.037

0.12

Average Expected Energy Use (mpge)

Passenger Car

Light Truck

Transit Bus

Hydrogen Fuel Cell

Gasoline Powered Car

Hydrogen Fuel Cell

Gasoline Powered Light Truck

Hydrogen Fuel Cell

Diesel Powered Transit Bus

81.2

29.3

49.2

21.5

12.4

3.86

 

Source: Plan for Fuel Cell Economic Development