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The Renewable Energy Institute
referred to as "Combined
Heat and Power" or "CHP"
is about 3 times more efficient than typical power plants
Heating and Power" and
"Cooling, Heating and Power for
are terms for "trigeneration."
Technologies, based in Houston, Texas, provides "turnkey"
cogeneration and trigeneration power
plant development services.
Cleaner, Greener Power & Energy Solutions project
development services are one of our specialties. These projects are
Kyoto Protocol compliant and generate clean energy and significantly
fewer greenhouse gas emissions. Unlike most companies, we are equipment
supplier/vendor neutral. This means we help our clients select the best
equipment for their specific application. This approach provides our
customers with superior performance, decreased operating expenses and
increased return on investment.
Technologies, located in Houston, Texas, provides
project development services that generate clean energy and
significantly reduce greenhouse
gas emissions and carbon
dioxide emissions. Included in this are our
products and services which includes renewable
energy technologies, waste to
energy, waste to watts™ and waste
heat recovery solutions. Other project development
technologies include; Anaerobic
Digester, Anaerobic Lagoon, Biogas
Recovery, BioMethane, Biomass
Gasification, and Landfill Gas
To Energy, project development services.
services provided by Cogeneration Technologies includes the following
power and energy project development services:
Engineering Feasibility & Economic Analysis Studies
Procurement and Construction
Engineering & Permitting
Funding & Financing Options; including Equity Investment, Debt
Financing, Lease and Municipal Lease
Savings Program with No Capital Investment from Qualified Clients
Party Ownership and Project Development
Tag (Renewable Energy Credit, Carbon Dioxide Credits, Emission
Reduction Credits) Brokerage Services; Application and Permitting
more information: call us at: 832-758-0027
are Renewable Energy
Technologies specialists and develop clean power and energy projects
that will generate a "Renewable
Energy Credit," Carbon
Dioxide Credits and Emission
Reduction Credits. Some of our products and services solutions
and technologies include; Absorption
Chillers, Adsorption Chillers,
Automated Demand Response, Biodiesel
Refineries, Biofuel Refineries,
Biomass Gasification, BioMethane,
Canola Biodiesel, Coconut
Biodiesel, Cogeneration, Concentrating
Solar Power, Demand Response
Programs, Demand Side
Conservation Measures, Energy
Master Planning, Engine Driven
Chillers, Geothermal Heatpumps,
Groundsource Heatpumps, Solar
CHP, Solar Cogeneration, Rapeseed
Biodiesel, Solar Electric
Heat Pumps, Solar
Electric Power Systems, Solar
Heating and Cooling, Solar
Trigeneration, Soy Biodiesel, Trigeneration,
and Watersource Heatpumps.
also known as combined heat and power (cogeneration) or CHP, and total
energy, is an efficient, clean, and reliable approach to generating
power and thermal energy from a single fuel source. That is,
cogeneration uses heat that is otherwise discarded from conventional
power generation to produce thermal energy. This energy is used to
provide cooling or heating for industrial facilities, district energy
systems, and commercial buildings. By recycling this waste heat,
cogeneration systems achieve typical effective electric efficiencies of
50% to 70% — a dramatic improvement over the average 33% efficiency of
conventional fossil-fueled power plants. Cogenerations' higher
efficiencies reduce air emissions of nitrous oxides, sulfur dioxide,
mercury, particulate matter, and carbon dioxide, the leading greenhouse
gas associated with climate change.
More About Cogeneration
Cogeneration now produces almost 10% of our nation's electricity, saves
its customers up to 40% on their energy expenses, and provides even
greater savings to our environment.
Cogeneration, as previously described above, is 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
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 100 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. Primary fuels commonly used
in cogeneration include natural gas, oil, diesel fuel, propane, coal,
wood, wood-waste and bio-mass. These "primary" fuels are
used to make electricity, a "secondary" fuel. This is why
electricity, when compared on a btu to btu basis, is typically 3-5 times
more expensive than primary fuels such as natural gas.
An example of a cogeneration process would be the automobile in which
the primary fuel (gasoline) is burned in an internal combustion engine -
this produces both mechanical and electrical energy (cogeneration).
These combined energies, derived from the combustion process of the
car's engine, operate the various systems of the automobile, including
the drive-train or transmission (mechanical power), lights (electrical
power), air conditioning (mechanical and electrical power), and heating
of the car's interior when heat is required to keep the car's occupants
warm. This heat, which is manufactured by the engine during the
combustion process, was “captured” from the engine and then
re-directed to the passenger compartment.
Due to competitive pressures to cut costs and reduce emissions of air
pollutants and greenhouse gasses, owners and operators of industrial and
commercial facilities are actively looking for ways to use energy more
efficiently. One option is cogeneration, also known as combined heat and
power (CHP). Cogeneration/CHP is the simultaneous production of
electricity and useful heat from the same fuel or energy. Facilities
with cogeneration systems use them to produce their own electricity, and
use the unused excess (waste) heat for process steam, hot water heating,
space heating, and other thermal needs. They may also use excess process
heat to produce steam for electricity production. Cogeneration currently
coexists with a regulated industry that is going through major
structural changes that may limit or expand its application.
The concept of cogeneration is not new. Early in this century, before
there was an extensive network of power lines, many industries had
cogeneration plants. As utilities became established and grew, most
states began to regulate them in order to limit their pricing power.
The Public Utilities Holding Act of 1935 (PUHCA), together with
amendments to the Federal Power Act (also in 1935), were the final steps
in protecting utility companies from competition. These laws created
vertically integrated utilities with responsibility for the production,
transmission, and distribution of power. In exchange for their exclusive
franchises (territories) and guaranteed revenues, utilities agreed to
government regulation of rates and service. Under these rules, more
investments in infrastructure and more sales meant more profits. As the
network of power lines grew and electricity from utilities became more
economical, industrial facilities bought more of their electricity from
utilities. However, many industries still had to generate process heat
on-site. The economies of scale that the utilities were able to obtain
at that time, as well as the availability of low-priced process heat
from cheap oil and gas, removed incentives to retain cogeneration
In the past three decades, however, the long-term trend of energy prices
generally moved upward. Building more and more large power plants no
longer provided economies of scale. This was a major factor in the
increasing use of cogeneration by commercial and industrial facilities.
The Public Utilities Regulatory Policies Act of 1978 (PURPA) provided
further encouragement for developers of cogeneration plants. Section 210
requires utilities to purchase excess electricity generated by "qualifying
facilities" (QFs) and to provide backup power at a reasonable
cost. QFs included plants that used renewable resources and/or
cogeneration technologies to produce electricity. PURPA cogenerators
must use at least 5% of their thermal output for process or space
heating (10% for facilities that burn oil or natural gas). In many
cases, this forced independent cogenerators to accept very low rates for
their steam production in order to become a qualifying
facility under PURPA. Another problem is the rate at which utilities
purchase a cogenerator’s excess power production.
Most states set the price at "avoided cost," or the cost to
the utility of producing that extra power. Utilities with excess power
generation capacity are often allowed to have extremely low avoided
costs. This practice has created artificial barriers to cogeneration as
well as to independent power generators.
The Energy Policy Act of 1992 (EPAct) tried to create a more competitive
marketplace for electricity generation. It created a new class of power
generators known as Exempt Wholesale Generators (EWGs). These are exempt
from PUHCA regulation and can sell power competitively to wholesale
customers. A cogeneration facility can be (but does not have to be) a QF
under PURPA and an EWG under EPAct. This happens when the facility is in
the exclusive business of wholesale power sales, and makes no retail
power sales to its "steam host" (customer).
A typical cogeneration system consists of an engine, steam turbine, or
combustion turbine that drives an electrical generator. A waste heat
exchanger recovers waste heat from the engine and/or exhaust gas to
produce hot water or steam. Cogeneration produces a given amount of
electric power and process heat with 10% to 30% less fuel than it takes
to produce the electricity and process heat separately.
There are two main types of cogeneration techniques: "Topping
Cycle" plants, and "Bottoming Cycle" plants.
A topping cycle plant generates electricity or mechanical power first.
Facilities that generate electrical power may produce the electricity
for their own use, and then sell any excess power to a utility. There
are four types of topping cycle cogeneration systems. The first type
burns fuel in a gas turbine or diesel engine to produce electrical or
mechanical power. The exhaust provides process heat, or goes to a heat
recovery boiler to create steam to drive a secondary steam turbine. This
is a combined-cycle topping system. The second type of system burns fuel
(any type) to produce high-pressure steam that then passes through a
steam turbine to produce power. The exhaust provides low-pressure
process steam. This is a steam-turbine topping system. A third type
burns a fuel such as natural gas, diesel, wood, gasified coal, or
landfill gas. The hot water from the engine jacket cooling system flows
to a heat recovery boiler, where it is converted to process steam and
hot water for space heating. The fourth type is a gas-turbine topping
system. A natural gas turbine drives a generator. The exhaust gas goes
to a heat recovery boiler that makes process steam and process heat. A
topping cycle cogeneration plant always uses some additional fuel,
beyond what is needed for manufacturing, so there is an operating cost
associated with the power production.
Bottoming cycle plants are much less common than topping cycle plants.
These plants exist in heavy industries such as glass or metals
manufacturing where very high temperature furnaces are used. A waste
heat recovery boiler recaptures waste heat from a manufacturing heating
process. This waste heat is then used to produce steam that drives a
steam turbine to produce electricity. Since fuel is burned first in the
production process, no extra fuel is required to produce electricity.
An emerging technology that has cogeneration possibilities is the fuel
cell. A fuel cell is a device that converts hydrogen to electricity
without combustion. Heat is also produced. Most fuel cells use natural
gas (composed mainly of methane) as the source of hydrogen. The first
commercial availability of fuel cell technology was the phosphoric acid
fuel cell, which has been on the market for a few years. There are about
50 installed and operating in the United States. Other fuel cell
technologies (molten carbonate and solid oxide) are in early stages of
development. Solid oxide fuel cells (SOFCs) may be potential source for
cogeneration, due to the high temperature heat generated by their
Cogeneration systems have been designed and built for many different
applications. Large-scale systems can be built on-site at a plant, or
off-site. Off-site plants need to be close enough to a steam customer
(or municipal steam loop) to cover the cost of a steam pipeline.
Industrial or commercial facility owners can operate the plants, or a
utility or a non-utility generator (NUG) may own and operate them.
Manufacturers use 90% of all cogeneration systems. Some industries and
waste incinerator operators who own their own equipment realize sizable
profits with cogeneration.
Another large-scale application of cogeneration is for district heating
and cooling. Many colleges, hospitals, office buildings and even cities,
that have extensive district heating and cooling systems, have at their
core, a cogeneration or trigeneration power plant. The University of
Florida has a 42 Megawatt (MW) gas turbine cogeneration plant, built in
partnership with the Florida Power Corporation. Some large cogeneration
facilities were built primarily to produce power. They produce only
enough steam to meet the requirements for qualified facilities under
PURPA. If no steam host is nearby, one can be built. For example, there
are large (80 MW) plants operating under PURPA that have large
greenhouses as "steam hosts." The greenhouses operate without
losing money only because their steam heat is virtually free of charge.
These types of plants are candidates to become EWGs in the new
Many utilities have formed subsidiaries to own and operate cogeneration
plants. These subsidiaries are successful due to the operation and
maintenance experience that the utilities bring to them. They also
usually have a long-term sales contract lined up before the plant is
built. One example is a 300 MW plant that is owned and operated by a
subsidiary co-owned by a utility and an oil company. The utility feeds
the power directly into its grid. The oil company uses the steam to
increase production from its nearby oil wells.
Cogeneration systems are also available to small-scale users of
electricity. Small-scale packaged or "modular" systems are
being manufactured for commercial and light industrial applications.
Modular cogeneration systems are compact, and can be manufactured
economically. These systems, ranging in size from 20 kilowatts (kW) to
650 kW produce electricity and hot water from engine waste heat. It is
usually best to size the systems to meet the hot water needs of a
building. Thus, the best applications are for buildings such as
hospitals or restaurants that have a year-round need for hot water or
steam. They can be operated continuously or only during peak load hours
to reduce peak demand charges, although continuous operation usually has
the quickest payback period.
Several companies also attempted to develop systems that burn natural
gas and fuel oil for private residences. These home-sized cogeneration
packages had a capacity of up to 10 kW, and were capable of providing
most of the heating and electrical needs for a home. As of May 2000,
none of the companies that developed these systems are selling these
units. Several fuel call manufacturers are targeting residential and
small commercial applications.
While cogeneration provides several environmental benefits by making use
of waste heat and waste products, air pollution is a concern any time
fossil fuels or biomass are burned. The major regulated pollutants
include particulates, sulfur dioxide (SO2), and nitrous oxides (NOx).
Water quality, while a lesser concern, can also be a problem. New
cogeneration plants are subject to an Environmental Protection Agency
(EPA) permit process designed to meet National Ambient Air Quality
Standards (NAAQS). Many states have stricter regulations than the EPA.
This can add significantly to the initial cost of some cogeneration
facilities located in urban areas.
Some cogeneration systems, such as diesel engines, do not capture as
much waste heat as other systems. Others may not be able to use all the
thermal energy that they produce because of their location. They are
therefore less efficient, and the corresponding environmental benefits
are less than they could be. The environmental impacts of air and water
pollution and waste disposal are very site-specific for cogeneration.
This is a problem for some cogeneration plants because the special
equipment (water treatment, air scrubbers, etc.) required to meet
environmental regulations adds to the cost of the project. If, on the
other hand, pollution control equipment is required for the primary
industrial or commercial process anyway, cogeneration can be
Even the environmental groups are on the cogeneration bandwagon. Since
its' founding, the Sierra Club has supported total energy
(cogeneration). See the Sierra Club's statement on energy policy.
Future Market Development
Several factors will affect the growth of cogeneration activities. They
include the initial cost of buying and bringing a cogeneration system
on-line, maintenance costs, and environmental control requirements. Some
electric utilities do not need additional electricity. They may have
excess generation capacity or a stable customer base. This leads to
lower "avoided cost" rates, which reduces the viability of
cogeneration projects that rely heavily on power sales to utilities.
The restructuring of the electric power generation and distribution
industry that is currently underway in many states, makes it more
attractive for developers to become independent power producers and to
build "electricity only" power plants, instead of cogeneration
plants. There has also been a great deal of pressure from utility and
industrial special interests to repeal or amend PURPA. If they are
successful, it could be difficult for new cogeneration projects to get
off the ground. Barring that development, improved technology and
cooperation among industries, businesses, utilities, and financiers
should provide impetus to the continued development of both cogeneration
projects and independent power production projects.
One significant impetus for cogeneration is the issue of global climate
change from global warming caused by the greenhouse effect, of which
fossil fuel combustion is a major contributor.
Cogeneration is the environmentally-friendly, economically-sensible way
to produce power, simultaneously saving significant amounts of money and
also dramatically reducing total greenhouse gas emissions.
Cogeneration technologies are conventional power generation systems with
the means to make use of the energy remaining in exhaust gases, cooling
systems, or other energy waste stream. Typical cogeneration prime movers
Boilers with steam turbines
Cogeneration offers energy, environmental, and economic benefits,
By improving efficiency, cogeneration systems can reduce fuel costs
associated with providing heat and electricity to a facility.
Improving power reliability
Cogeneration systems are located at the point of energy use. They
provide high-quality and reliable power and heat locally to the energy
user, and they also help reduce congestion on the electric grid by
removing or reducing load. In this way, cogeneration systems effectively
assist or support the electric grid, providing enhanced reliability in
electricity transmission and distribution.
Reducing environmental impact
Because of its improved efficiency in fuel conversion, cogeneration
reduces the amount of fuel burned for a given energy output and reduces
the corresponding emissions of pollutants and greenhouse gases.
Conserving limited resources of fossil fuels
Because cogeneration requires less fuel for a given energy output, the
use of cogeneration reduces the demand on our limited natural
resources—including coal, natural gas, and oil—and improves our
nation's energy security.
Where Can cogeneration Be Used?
Cogeneration installations are most likely to be economically viable at
locations where the following characteristics exist:
* Coincident demand for electricity and thermal energy (i.e., steam,
heating, or cooling) during most of the year.
* Access to fuels, including natural gas, biomass, and/or by-product
The following are typical markets for cogeneration:
Energy-intensive industries, including the chemical, refining, forest
products, food, and pharmaceutical sectors.
District energy systems that distribute heat or chilled water to a
network of buildings. Such systems show the greatest promise in downtown
areas, industrial parks, college campuses, military bases, and other
large institutional facilities.
High power reliability/quality applications, such as Internet or
telecommunications data centers requiring high-quality, reliable power
and substantial cooling capacity.
Institutional markets, including hospitals, hotels, and convention
centers where large year-round demands exist for electricity, heating,
Abandoned industrial sites, or brownfields, where cogeneration-based
systems can provide the energy infrastructure for "power
parks," facilitating economic redevelopment of underutilized
Commercial buildings—as building-scale cogeneration technologies
become better integrated and increasingly cost-effective, this market
offers large potential for new applications.
A small sample of successful businesses now using cogeneration
Agriculture, apartment buildings, auto/car dealerships, casinos,
cold storage facilities, communications sites, convenience stores,
credit card processing facilities, customer service centers, dairies,
fabrication plants, feed yards, foundries, golf courses, government
buildings, commercial greenhouses and nurseries, grocery stores,
hospitals, hotels, ice skating rinks, industrial parks, ISP's,
landfills, laundries/laundromats, malls, manufacturing plants, military
bases and installations, motels, nursing homes, oil & gas leases,
office buildings, paper & pulp, parking garages, printing companies,
processing plants, radio stations, resorts, restaurants, retail stores,
retirement homes, schools, server farms, shopping centers, sports
complexes, steel manufacturing, supermarkets, television stations,
universities, warehouses, waste treatment facilities, wineries
The U.S. Department of Energy (DOE) and the U.S.
Environmental Protection Agency Supports Cogeneration.....
Because the average efficiency of the fossil-fueled power plants in the
U.S. is around 30-33% and has remained virtually unchanged since the
1930's. This means that two-thirds of the energy in the fuel is lost as
heat. Cogeneration systems recycle this waste heat and convert it to
useful energy and achieve effective electrical efficiencies of 50% to
70%. This improvement reduces emissions of sulfur dioxide, nitrous
oxide, mercury, particulate matter, and carbon dioxide, the leading
greenhouse gas associated with climate change. In addition to reducing
air pollution, cogeneration conserves our limited fossil fuel resources,
thereby increasing our nation's energy self-sufficiency.
call us at: 832-758-0027
* Some of the above information from the Department
of Energy website with permission.