Combined Heat and Power

Mar 05, 2006 Print Article

Co-generation, now referred to as “Combined Heat and Power (CHP)” is the sequential or simultaneous generation of multiple forms of useful energy (usually mechanical and thermal) in a single, integrated system.1 CHP is a proven technology and is considered one of the most cost effective sources of clean energy generation based on CHP deployment and capacity in the U.S. and globally today. CHP is a form of energy recycling. CHP techniques and technologies use “wasted energy” for making steam, heating water or refreshing a desiccant humidity control device.2

CHP is a form of “energy recycling” and is considered a category of alternative energy methods and techniques likely to advance significantly over the next 3-5 years. CHP systems consist of a number of individual components-prime mover, generator, heat recovery and electrical interconnection-configured into an integrated whole.”3 Combined cycle gas turbines, internal combustion engines, combustion turbines, biomass gasification, geothermal, sterling engines as well as fuel cells are suitable for CHP.

Source: National CHP Roadmap, 2001

CHP — What’s in a Name? Combined heat and power. Cooling, heating, and power. District heating and cooling. District energy systems. Cogeneration. Buildings cooling, heating, and power. These are similar terms for a single concept known for more than a century. In converting fuel to electricity, approximately two-thirds of the energy input is released to the environment during the conversion process and not used for productive purposes. Technologies that use this “wasted energy” for making steam, heating water, or refreshing a desiccant humidity control device are known as CHP systems. CHP makes greater use of the fuel inputs by producing multiple products – electricity and usable thermal energy. The average efficiency of the typical power plant in the U.S. is approximately 33 percent; however, CHP systems can reach efficiency levels of 70 percent or greater. CHP is considered by many as the best pollution prevention practice in the energy generation industry.[/pullquote]

In CHP systems, thermal energy in various exhaust streams from power generation equipment is recovered for operating equipment for space and/or process cooling, heating or controlling humidity in facilities, by using absorption chillers, desiccant dehumidifiers, or heat recovery equipment for producing steam or hot water. These integrated systems are known by a variety of acronyms: CHP, CHPB (Cooling, Heating and Power for Buildings), CCHP (Combined Cooling Heating and Power), BCHP (Buildings Cooling, Heating and Power), and IES (Integrated Energy Systems).4

CHP is a form of “Distributed Generation”. Distributed generation can be defined as “the installation and operation of electric power generation units connected directly to the distribution network or connected to the network on the customer site of the meter.”5 For several excellent examples of CHP applications including pictures of the technology environment, see Ted Bronson’s CHP Overview:

Source: National CHP Roadmap, 2001

In 2001, Texas had the largest installation of distributed generation facilities in the nation.6 This includes 137 CHP sites producing 16.7 GW in Texas.7 98% of these CHP sites are industrial plants.8

CHP is a proven process that is mature in large industrial plants. CHP is in the early adoption phase in mid-tier markets including hospitals, universities, office buildings and manufacturing facilities and it is an emerging method in residential applications. Micro-CHP (mCHP) units for individual homes are now sold in Germany, Japan and most recently in the U.S..

Micro-CHP can deliver 10% to 20% cost savings compared to generating heat and electricity separately in residential applications.9 mCHP can be developed using a variety of prime mover technologies, such as Stirling engines, Rankine cycle generators, reciprocating engines and fuel cells.10

CHP technologies are a potentially disruptive technology because they can change the economics of energy consumption, generation and recycling. Barriers to this possibility are largely regulatory, industrial and municipal policy. Current environmental concerns about global warming, security, war and economics may fuel CHP’s emergence after decades of industrial application into the mid-market (hospitals, schools, etc) by 2010, in emergency relief operations (microCHP) by 2010 and in residential applications (microCHP) by 2015.


Jobs related to CHP fall into three categories: Professional Engineering, Plant Operations and Trades (such as mechanical, electrical and instrumentation technologists).11 Entry level jobs exist in the plant operations and trade skills domains. All three levels (engineering, operations and trades) require CHP-specific training for design, operations and maintenance post-installation because CHP systems require the integration of many power plant technologies and each operational environment is relatively unique (in older facilities integrating legacy power generation systems and new highly-automated power generation systems).

Over the past 5 years, the University of Texas at Austin completed a $20MM CHP power plant upgrade in order to increase efficiency and to reduce noxious air emissions.12 All UT power plant personnel (engineers, operators and trades) are required to complete between 20 and 280 hours of custom training developed in-house at UT. (see footnote 9) Today, CHP certified technicians and technologists are very rare and CHP-specific certification would provide a distinct competitive advantage for trade, operations and engineering candidates applying for jobs at UT (see footnote 9) and possibly those applying for Texas power plant positions in facilities where CHP is online today.

Specific skilled trade jobs of interest to Community and Technical Colleges (CTCs) include: Electrical Instrumentation Technician (High Voltage Electrical Systems and Digital Controls), Instrumentation Technologists (Programmable Logic Controls and Systems Integration) and Plant Maintenance Mechanics (Turbines, Boilers and Distribution Maintenance).


CHP energy recycling exists in virtually every sector of the economy, particularly industrial plants, commercial buildings, federal facilities and district energy systems. (see footnote 2) In the Gulf Coast Region, approximately 98% of CHP energy is located in industrial facilities accounting for 30% of U.S. CHP capacity. Significant market and regulatory barriers at the state and federal level are hampering development of CHP plants.13 To understand the economics and regulatory environment of CHP in detail see: Resource Directory; Gulf Coast CHP. Individual utility interconnection and tariff practices continue to be significant barriers faced by combined heat and power (CHP) projects in Texas.14 Since 1995 the pace of CHP installations has stalled due to uncertainties of the changing electricity marketplace.15 The higher the differential between the cost of buying electric power from the grid and the cost of natural gas, the more attractive the savings and payback associated with CHP become.16


The timing for CHP specific training is undetermined. CTCs are encouraged to contact industrial plants in their service region to gauge the market demand for CHP curriculum and/or certification. CTCs should especially scan the local environment for emerging CHP implementations in the mid-market including hospitals, universities, office buildings, and manufacturing facilities. The scale of the UT implementation impacting 80 staff members with a requirement for 20-280 hours of custom, in-house training is an indicator of the need for CHP specific training when CHP systems are installed in the mid-market.

Factors that may influence the increased adoption of CHP include: increasing energy costs; increased use of Liquefied Natural Gas (LNG) in connection with large turbines (similar to jet engines) such as Caterpillar’s “Solar Turbines” used for CHP; policies requiring power plants to reduce emissions of sulfur dioxide, nitrogen oxides and mercury; and further destabilization of energy supply (blackouts and brownouts).17

CHP Expansion Helps Optimize Natural Gas Supplies and Infrastructure

Energy Information Administration

In 2003, U.S. CHP capacity was 77GW-more than half-way to the goal of 92GW by 2010 set out by the U.S. EPA, DOE and the U.S. CHPA alliance as part of the CHP Roadmap in 1998.18 Today, CHP systems account for 1/3 of the electricity generated from gas19, therefore, the relationship between CHP and LNG should be investigated.

Figure 1. CHP Expansion Helps Optimize Natural Gas Supplies and Infrastructure

Source: Energy Information Administration in Progress of the CHP Industry in Removing Barriers to Implementation of CHP, Jimison, 2003.

As CHP capacity rises and incentives are provided for mid-market firms to utilize CHP, CTCs may have an opportunity to partner with power plant owner-operators for training and possibly certification related to CHP energy recycling.


CHP curriculum is relevant to CTCs; however, there does not appear to be a high degree of employment opportunity in the near-term. CHP is closely related to existing process technology, instrumentation and traditional trades (mechanical and electrical) taught in Texas CTCs. Local CHP implementations in a single industrial plant or 1-3 large mid-tier campus implementations (hospital, university, etc.) in one service area could justify new curriculum investments.

Skill Sets

CHP implementations require skilled trades such as electrical and mechanical technicians to integrate new knowledge, skills and abilities (KSA) related to “microelectronics” and “automatic control systems” with their traditional trades. This requirement is functionally similar to the requirement for automotive, heavy equipment and aerospace mechanics to evolve from mechanics associated with “turning a wrench and screwdriver” to technicians and technologists who manufacture, install, operate and maintain microelectronics-based systems in automobiles, heavy equipment and aviation-space vehicles. This functional integration of mechanics, electronics and computing is known as “mechatronics”.

We do not yet have language to describe the generalized application of mechatronics to trade skills such as mechanical or electrical systems technicians who work in CHP-based energy power plants; however, the impact of such a transformation in energy systems and related fields just now experiencing diffusion of embedded electronics may be understood from the recent history of the same transformation in the automotive, heavy equipment and aerospace industries. The diffusion of “automatic control systems” facilitates a transformation of trade skills to encompass electronic and computer systems knowledge, skills and abilities (KSA).

In the context of CHP, these industrial control systems are integrated with energy power plant systems; therefore, the knowledge base required is broad and systemic by nature. Carmagen has developed a four-day CHP curriculum designed for power plant personnel. The curriculum includes: Steam Power Plant Basics; Rankine cycle including reheaters, condensers, deaerators, regeneration; Steam Turbine Basic Components and Main Systems; Steam Turbine Governing System Basics; Gas Turbines and Fuel Systems; Combined Cycles and Other GT Cycle Modifications; Gas Turbine Intake and Exhaust Systems; Gas Turbine Instrumentation and Control (I&C) Systems; Gas Turbine Emission Guidelines and Control Methods; Gas Turbine Performance Verification and Maintenance; Generator, Exciter, and Other Electrical System Basics; Combined Cycle and Co-Generation Plant Basics; and Economics of Combined Cycle and Co-Generation Plants.

Summary Performance Indicators

Recommendation: This topic is not recommended for further study due to a lack of sufficient near-term employment opportunities within Texas.

Jobs: Relatively low number of new jobs within the next three to five years.

Trends: Energy, security and environmental concerns fueling adoption of techniques and technologies to recycle energy. CHP is currently the only way to significantly reduce carbon emissions. CHP is mature in industrial plants and in the early adoption phase of the mid-market (large campuses such as universities or hospitals).

Timing: The timing for CHP specific training is undetermined. CTCs are encouraged to contact industrial plants in their service region to gauge the market demand for CHP curriculum and/or certification. CTCs should especially scan the local environment for emerging CHP implementations in the mid-market including hospitals, universities, office buildings and manufacturing facilities.

Relevance: CHP is highly related to existing process technology, instrumentation and traditional trades (mechanical and electrical) taught in Texas CTCs. Local CHP implementations in a single industrial plant or 1-3 large mid-tier campus implementations (hospital, university, etc.) in one service area could justify new curriculum investment. CHP system and process knowledge is systemic but specific to CHP and energy recycling.

Transportability: CHP requires integration of KSAs from process technology, instrumentation and traditional trades (mechanical and electrical). Generalized curriculum may be created around “energy recycling” and/or “mechatronics”. The highest level of abstraction of CHP KSAs is mechatronics (integrated mechanical, electronic and computer systems) similar to automotive, heavy equipment and aerospace.

  11. Juan Ontiveros, Director, Utilities and Energy Management, UT Austin, Interview by Brazell
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