Stack Gas

Clean Combustion

Biomass Gasification  *  Clean Coal Technology  *  Coal Liquefaction  *  Coal to Gas  *  Coal to Natural Gas

Emissions Abatement  *  Emissions Engineering  *  Flare Gas Recovery  *  Fuel Switching  *  Gas to Power

Greenhouse Gas Emissions  *  Nitrogen Oxides  *  Oxycombustion  *  Synthesis Gas  *  Zero Emission Power

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Stack Gas

"The 'Holy Grail' for Energy is 'Net Zero Energy'
which is
'Way Beyond Solar!'"

What is "Stack Gas?"

A "stack gas" or flue-gas stack, is an "industrial-strength" chimney through which product of combstion (combustion gases - also referred to as "flue gases") are dispersed to the atmosphere.

Stack gases are produced when fossil fuels, such as coal, diesel, oil, or natural gas is combusted within industrial furnaces or power boilers such as those found at Central Power Plants.

Stack gases are primarily composed of carbon dioxide (CO2) and water vapor as well as nitrogen and the excess oxygen 
remaining from the intake combustion air. These stack gases also contain small percentages of "
hazardous air pollutants"
such as particulate matter (PM), carbon monoxide (CO), nitrogen oxides (NOx) and sulfur oxides (SOx).

What is Clean Combustion?

Clean Combustion includes fuels and technologies that do not require emissions abatement such as Selective Catalytic Reduction, scrubbers or other equipment needed to reduce hazardous air pollutants. In addition to reducing/eliminating hazardous air pollutants, the EPA is now requiring certain companies and industries to begin reducing their greenhouse gas emissions.


Recovery of "Waste Heat Stack Gases"
Waste Heat Recovery 
and Utilized in Cogeneration and 
power and energy systems

In most cogeneration and trigeneration power and energy systems, the exhaust gas from the electric generation equipment is ducted to a heat exchanger to recover the thermal energy in the gas. These heat exchangers are air-to-water heat exchangers, where the exhaust gas flows over some form of tube and fin heat exchange surface and the heat from the exhaust gas is transferred to make hot water or steam. The hot water or steam is then used to provide hot water or steam heating and/or to operate thermally activated equipment, such as an absorption chiller for cooling or a desiccant dehumidifer for dehumidification.

Many of the waste heat recovery technologies used in building co/trigeneration systems require hot water, some at moderate pressures of 15 to 150 psig. In the cases where additional steam or pressurized hot water is needed, it may be necessary to provide supplemental heat to the exhaust gas with a duct burner.

In some applications air-to-air heat exchangers can be used. In other instances, if the emissions from the generation equipment are low enough, such as is with many of the microturbine technologies, the hot exhaust gases can be mixed with make-up air and vented directly into the heating system for building heating.

In the majority of installations, a flapper damper or "diverter" is employed to vary flow across the heat transfer surfaces of the heat exchanger to maintain a specific design temperature of the hot water or steam generation rate.


Typical Waste Heat Recovery Installation

In some cogeneration and trigeneration designs, the exhaust gases can be used to activate a thermal wheel or a desiccant dehumidifier. Thermal wheels use the exhaust gas to heat a wheel with a medium that absorbs the heat and then transfers the heat when the wheel is rotated into the incoming airflow.

A professional engineer should be involved in designing and sizing of the Waste Heat Recovery section. For a proper and economical operation, the design of the heat recovery section involves consideration of many related factors, such as the thermal capacity of the exhaust gases, the exhaust flow rate, the sizing and type of heat exchanger, and the desired parameters over a various range of operating conditions of the cogeneration or trigeneration system — all of which need to be considered for proper and economical operation.

The Market and Potential for Waste Heat Recovery technologies and solutions

There are more than 500,000 smokestacks in the U.S. that are "wasting" heat, an untapped resource that can be converted to energy with Waste Heat Recovery technologies.

About 10% of these 500,000 smokestacks represent about 75% of the available wasted heat which has a stack gas exit temperature above 500 degrees F. which could generate approximately 50,000 megawatts of electricity annually and an annual market of over $75 billion in gross revenues before tax incentives and greenhouse gas emissions credits.

Waste Heat Recovery technologies represent the least cost solution which provides the greatest return on investment, than any other possible green energy technology or "carbon free energy" opportunity!


Clean Power Generation

Running on "green fuel" such as Biomethane, B100 Biodiesel, Synthesis Gas or natural gas, our CHP Systems are the greenest "clean power generation" systems available.

With Natural Gas at approximately $3.00/mmbtu, our Clean Power CHP Systems  generate power for about $0.03 / kWh (fuel cost).

With operations & maintenance added, that's  about 4.5 cents /kWh - or approximately 50% - 60% less than what most commercial customers are paying, on average, for their electricity.

CHP Systems
(Cogeneration and Trigeneration) Plants 
Have Very  High Efficiencies, Low Fuel Costs & Low Emissions

The CHP System below is rated at 900 kW with a 
heat rate of 4100 btu/kW & system efficiency of 92%.

The CHP System below features: (2) Natural Gas Engines @ 450 kW each 
on one skid with optional Selective Catalytic Reduction system 
which removes Nitrogen Oxides to "non-detect."



A CHP System may be the best solution for your company's economic and environmental  sustainability as we "upgrade" natural gas to clean power with our clean power generation solutions.  CHP Systems and Dispersed Generation power plants are an ideal solution for data centers, district energy systems electric utilities, electric co-ops, electrical sub-stations, energy service companies, food processing plants, hospitals, military bases and  universities among many others. 

High-efficiency CHP Systems eliminate blackouts, electric grid supply problems and significantly reduce greenhouse gas emissions and hazardous air pollutants associated with electric power generation at central power plants.  Our emissions abatement solutions reduce nitrogen oxides (NOx) to "non-detect" and can be installed and operated in most EPA non-attainment regions!

What is "Cogeneration"?

Did you know that 10% of our nation's electricity now comes from "cogeneration" plants?

And because cogeneration is so efficient, it saves its customers up to 40% on their energy expenses, and provides even greater savings to our environment through significant reductions in fuel usage and much lower greenhouse gas emissions.

Cogeneration - also known as “combined heat and power” (CHP), cogen, district energy, total energy, and combined cycle, is the simultaneous production of heat (usually in the form of hot water and/or steam) and power, utilizing one primary fuel such as natural gas, or a renewable fuel, such as Biomethane, B100 Biodiesel, or Synthesis Gas.

Cogeneration technology is not the latest industry buzz-word being touted as the solution to our nation's energy woes. Cogeneration is a proven technology that has been around for over 120 years!

Our nation's first commercial power plant was a cogeneration plant that was designed and built by Thomas Edison in 1882 in New York. Our nation's first commercial power plant was called the "Pearl Street Station."

What is "Trigeneration"?

Trigeneration is the simultaneous production of three forms of energy - typically, Cooling, Heating and Power - from only one fuel input. Put another way, our trigeneration power plants produce three different types of energy for the price of one.

Trigeneration energy systems can reach overall system efficiencies of 86% to 93%.  Typical "central" power plants, that do not need the heat generated from the combustion and power generation process, are only about 33% efficient.

Trigeneration Diagram & Description
Trigeneration Power Plants' Have the Highest System Efficiencies and are 
About 300 % More Efficient than Typical Central Power Plants

Trigeneration plants are installed at locations that can benefit from all three forms of energy.  These types of installations that install trigeneration energy systems are called "onsite power generation" also referred to as "decentralized energy."   

One of our company's principal's first experience with the design and development of a trigeneration power plant was the trigeneration power plant installation at Rice University in 1987 where our trigeneration development team started out by conducting a "cogeneration" feasibility study.  The EPC contractor that Rice University selected installed the trigeneration power which included a 4.0 MW Ruston gas turbine power plant, along with waste heat recovery boilers and Absorption Chillers.  A "waste heat recovery boiler" captures the heat from the exhaust of the gas turbine.  From there, the recovered energy was converted to chilled water - originally from (3) Hitachi Absorption Chillers - 2 were rated at 1,000 tons each, and the third Hitachi Absorption Chiller was rated at 1,500 tons. The Hitachi Absorption Chillers were replaced shortly after their installation by the EPC company.  The first trigeneration plant at Rice University was so successful, they added a second 5.0 MW trigeneration plant so today, Rice University is now generating about 9.0 MW of electricity, and also producing the cooling and heating the university needs from the trigeneration plant and circulating the trigeneration energy around its campus.

Trigeneration Chart
Trigeneration's "Super-Efficiency" compared 
with other competing technologies
As you can see, there is No Competition for Trigeneration!

Our trigeneration power plants are the ideal onsite power and energy solution for customers that include:  Data Centers, Hospitals, Universities, Airports, Central Plants, Colleges & Universities, Dairies, Server Farms, District Heating & Cooling Plants, Food Processing Plants, Golf/Country Clubs, Government Buildings, Grocery Stores, Hotels, Manufacturing Plants, Nursing Homes, Office Buildings / Campuses, Radio Stations, Refrigerated Warehouses, Resorts, Restaurants, Schools, Server Farms, Shopping Centers, Supermarkets, Television Stations, Theatres and Military Bases.

At about 86% to 93% net system efficiency, our trigeneration power plants are about 300% more efficient at providing energy than your current electric utility. That's because the typical electric utility's power plants are only about 33% efficient - they waste 2/3 of the fuel in generating electricity in the enormous amount of waste heat energy that they exhaust through their smokestacks.

Trigeneration is defined as the simultaneous production of three energies: Cooling, Heating and Power.  Our trigeneration  energy systems use the same amount of fuel in producing three energies that would normally only produce just one type of energy. This means our customers that have our trigeneration power plants have significantly lower energy expenses, and a lower carbon footprint.


Stack Gas

Carbon Emissions  CHP Systems  *  Clean Coal Technology  *  Coal to Gas  Coal to Natural Gas

Dry Sorbent Injection  EcoGeneration  *  Emissions Abatement  *  Emissions Engineering

FuelSwitching  *  Greenhouse Gas Emissions  *  Greenhouse Gas Reporting

Hazardous Air Pollutants Net Zero Energy  *  New Source Review  *  Trigeneration

"Changing the Way the World Makes and Uses Energy" SM

Austin, Texas








Stack Gas, Clean Combustion and Emissions Abatement

Carbon Emissions  CHP Systems  *  Clean Coal Technology  *  Coal to Gas  Coal to Natural Gas

Dry Sorbent Injection  EcoGeneration  *  Emissions Abatement  *  Emissions Engineering

FuelSwitching  *  Greenhouse Gas Emissions  *  Greenhouse Gas Reporting

Hazardous Air Pollutants Net Zero Energy  *  New Source Review  *  Trigeneration


CHP Systems  *  Clean Power Generation  *  Emissions Abatement  *  OxyCombustion

Pollution Free Power  *  Solar Cogeneration  *  Trigeneration


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