Background

The United States has 100+ years of coal reserves, but coal’s high pollutant content makes it one of the most environmentally unfriendly energy sources. Coal combustion releases a wide variety of harmful pollutants, including SOx, NOx, fly-ash, and Mercury. Coal’s high carbon content produces large amounts of CO2 when burned, significantly contributing to harmful greenhouse gases. The toxic pollutants and CO2 are all released in the stack exhaust, where they are hard to isolate and capture and end up spread over large areas. Pollution control equipment is expensive and does not capture all pollutant emissions. If we can find an environmentally friendly way to use coal, we can solve our energy problems for the near future while we develop renewable sources of energy.

Power generation based on coal combustion is a 19th century technology that is fundamentally inefficient. Coal combustion power plants inherently have a low efficiency since the second law of thermodynamics requires that most of the fuel energy is lost as waste heat in the power generating cycle. Legacy power plants have efficiencies as low as 25% while more modern coal-fired power plants improve the efficiency to only 35-40%. To make up for the low efficiency, coal-combustion power plants must burn large amounts of fuel – generating even more pollutants.

There is an urgent need for a new pollution-free electrical generation technology that can efficiently utilize US’ abundant coal reserves.

 

The Technology

SARA’s Abundant Pollution-Free Electrical Generation (APEG™) is a breakthrough technology for generating electricity directly from coal using electrochemical reactions. There is no combustion, which means no smoke stacks and a much lower potential environmental impact. There is no thermodynamic cycle with a fuel cell so efficiencies are much higher than existing steam based power plants. Our APEG system uses a molten hydroxide electrolyte, with the coal itself acting as the anode and air bubbling through the electrolyte acting as the cathode.

SARA has developed the APEG technology over a number of years and numerous prototype designs. To date, the funding for the development has come from SARA internal research, Department of Energy, American Electric Power, and Electric Power Research Institute (EPRI). APEG is currently at Technology Readiness Level (TRL) 3 since SARA has successfully demonstrated 10’s of Watts of power output, 100+ hours of continuous operation, experimentally validated the electrochemical reactions, and demonstrated operation with coal derived fuels. SARA already has one patent on the technology with a second patent pending. The technology is now ready for transition to TRL6.

 

 

 

 

 

 

 

 

 

 

 

 

 

SARA’s APEG™ technology has been developed over multiple generations of successful prototypes.

The Applications

SARA’s APEG™ technology will revolutionize the generation of electrical power from coal and other carbon based fuels. The primary applications will be:

• Large-scale regional generation.

• Distributed micropower electrical generation.

• Load leveling for intermittent renewable energy.

​

​

​

​

​

​

​

​

​

​

​

​

​

​

 

 

 

SARA's vision for a utility scale power plant. APEG units are stacked to produce utility scale voltages and powers.

The Advantages

APEG has numerous advantages when compared to conventional coal fired power plants:

• Up to twice the power production efficiency of conventional coal power plants, resulting in about 50% reduction in CO2 emissions.

• Pollution-free since all pollutants such as fly-ash, sulfur, and mercury are captured in the electrolyte.

• 100% capture of CO2 emissions (a known greenhouse warming gas) since it exits the fuel cell as a concentrated stream without impurities.

• Is not dependent on proximity to large bodies of water as the APEG does not boil water or generate large amount of waste heat.

• Scalable from micropower distributed generation up to utility power levels.

• Power output can be rapidly increased or decreased, making it an ideal companion to intermittent renewable energy sources.

• Lower capital cost and cost of energy as compared to conventional coal plants since it does not depend on exotic material.

​