{"id":968,"date":"2015-01-07T06:39:08","date_gmt":"2015-01-07T06:39:08","guid":{"rendered":"http:\/\/energysystemsdevelopment.iteratemarketing.com\/?page_id=968"},"modified":"2015-03-24T08:08:27","modified_gmt":"2015-03-24T08:08:27","slug":"faq","status":"publish","type":"page","link":"https:\/\/www.esdevelop.com\/about\/faqs\/faq\/","title":{"rendered":"Cogen FAQs"},"content":{"rendered":"

What is Co-generation (COGEN)?<\/h3>\n

COGEN <\/strong>is a process where you can generate two forms of energy, electricity and heat, from a single fuel source. The basic idea is to burn Natural Gas to drive a co-generation engine (a small jet engine) which provides the torque to spin a generator which produces the electricity. Co-generation occurs when you capture and reuse the engine’s exhaust waste heat (exiting at 535o <\/sup>F) to assist with space heating for buildings, hot water heating, pool and spa heating, absorption cooling, steam production and centralized heating\/cooling.<\/p>\n

Figure 1.<\/em><\/strong><\/p>\n

\"cogen<\/p>\n

What is a Heat Exchanger?<\/h3>\n

A heat exchanger is a specialized device that assists in the transfer of heat from one fluid to the other. In some cases, a solid wall may separate the fluids and prevent them from mixing. In the most efficient heat exchangers, the surface area of the wall between the fluids is maximized while simultaneously minimizing the fluid flow resistance. Fins or corrugations are sometimes used with the wall in order to increase the surface area and to induce turbulence<\/a>. Perhaps the most commonly known heat exchanger is a car radiator, which cools the hot radiator fluid<\/a> by taking advantage of airflow over the surface of the radiator.In the case of co-generation engines, the energy from exhaust waste heat is transferred to assist with space heating, hot water heating, steam production, chemical processing, and cooling with absorption chillers.<\/p>\n

What is an Absorption Chiller?<\/h3>\n

The waste heat vaporizes a chemical in a vacuum into a gaseous state. The gas cools when it expands into the gaseous state and is then routed through a heat exchanger as a refrigerant. The refrigerant then cools the fluid that is used in a cooling cycle.<\/p>\n

The two most common refrigerant\/ absorbent mixtures used in absorption chillers are water\/lithium bromide and ammonia\/water.<\/p>\n

Compared with mechanical chillers, absorption chillers have a low coefficient of performance (COP = chiller load\/heat input). However, absorption chillers can substantially reduce operating costs because they are powered by low-grade waste heat. Vapor compression chillers, by contrast, must be motor- or engine-driven.<\/p>\n

Absorption Chiller\/Refrigeration<\/strong> – An absorption chiller is a transfer heat device which uses the co-generation engine waste heat to drive the cooling process.<\/p>\n

Can COGEN help me generate my own power?<\/h3>\n

A Natural Gas fired Co-generation system will enable you to generate your own on-site power and operate off the utility power grid. It allows you to operate as a stand-alone system, and use utility power only when it is needed.<\/p>\n

COGEN can self-start without outside power and load follow your power demand needs as they fluctuate during the day. If your demand exceeds the COGEN system capacity, it will switch in the parallel use of utility power (seamlessly) to meet the excess demand.<\/p>\n

Can I avoid utility power failures by operating off the utility power grid?<\/h3>\n

COGEN improves power reliability by reducing or eliminating a building’s dependence on the electric power grid, and makes power outages improbable.<\/p>\n

During major grid failures, COGEN can continue to operate up to its maximum design capacity. For example, over 30 hospitals with COGEN continued routine operations during the August 2003 California power blackout.<\/p>\n

Where the grid is at or near capacity, COGEN will reduce the grid’s load, thus increasing grid reliability and homeland security.<\/p>\n

Will COGEN generate power at a lower cost than the utility rates?<\/h3>\n

The gas price vs. electric rate is known as the \u201cSparks Spread\u201d. The cost of Natural Gas has dropped dramatically (by 66%) in the past 4 years. This has made the use of Natural Gas co-generation systems to generate electricity very cost competitive.<\/p>\n

The use of low cost Natural Gas allows COGEN to generate power at a cost that is 40% to 60% lower than the standard utility rates per KWH. (e.g. The COGEN rate could be less than 5 cents per KWH vs. today’s current Utility rates which can range from 10 cents to 20 cents per KWH. This represents a minimum savings of 50% if your utility rate is 10 cents per KWH, and more if your utility rate is higher.<\/p>\n

What Kind of Savings Will COGEN Generate?<\/h3>\n

Savings Are Substantial. <\/strong>Assuming a minimum threshold of energy consumption and energy costs that justifies the capital expenditure, COGEN can generate savings from 50% to 60% of current operating costs. A recent typical client example is as follows:<\/p>\n