Reduced Operating Costs via High Efficiency CHP, Distributed Generation or Standby Power
Many industrial facilities such as manufacturing plants, refineries and regional district heating plants reduce operating costs by implementing a Caterpillar combined heat and power (CHP) system (also known as cogeneration) using clean pipeline natural gas as a fuel source. Cat® gas generator sets can simultaneously provide electricity for electrical loads and heat energy for a facility's thermal requirements. Whereas separate grid electricity and natural gas boilers often provide less than 50 percent efficiency, Cat CHP projects offer:
- Energy efficiency up to 90 percent
- Reduced energy costs versus separate heat and electrical generation systems
- Reduced emissions versus separate heat and electrical generation systems
Where the capture and use of waste heat is not viable, many industrial facilities may still benefit financially via distributed generation (DG), or locally producing power to meet one's own requirements, or via a standby power plant. This is especially true when any of the following apply:
- The local electric grid is unreliable
- Natural gas is an inexpensive alternative to grid electricity
- Generators can be applied during peak times of day to avoid high electrical utility demand charges (also know as peak shaving)
How It Works
Any Cat natural gas fueled engine can be configured specifically for applications involving heat recovery. The engine drives a Cat gas generator set to produce electricity, while jacket water and/or exhaust cooling circuits are fed through heat exchangers (radiators in the case where CHP is not employed) to transfer the waste heat from the engine to a customer's hot water or steam circuit. That hot water or steam can then be effectively used for the purposes of a facility's process or HVAC requirements, including facility cooling (known as trigeneration) when implementing an absorption or adsorption chiller.
Caterpillar provides customized CHP package proposals, including the required mechanical equipment and controls to capture and transfer the engine thermal energy to an industrial facility. In addition, Caterpillar offers exhaust emissions after treatment for highly regulated emission environments and utility grade Cat paralleling switchgear to sell excess electricity generated to the local electric grid.
The total energy cost savings of such systems can more than offset the total owning and operating costs, delivering a payback in as little as two to three years, depending on local energy pricing and policies.
How Distributed Generation and Standby Power Work
When power is produced locally without heat recovery from the engine, Caterpillar provides radiators to provide proper cooling to the engine jacket water, engine oil and aftercooler water circuits. Cat paralleling switchgear is employed to allow generators to operate with one another or in conjunction with a local utility power source.
Although diesel fueled emergency power systems will always be the solution of choice for life safety emergency standby systems, there has been an increasing move toward natural gas fueled standby power systems in recent years. Typically installed with an automatic transfer switch (ATS) or paralleling switchgear control for multiple generator sets, these systems sense when a utility outage occurs and automatically start the backup power system and transfer power to the emergency source. When normal grid power returns, the control system automatically switches back and shuts down the emergency generator.