Mechanical energy conversion of gas into electricity using a gas engine will produce waste heat which can be utilized as a co-product. With co product will increase the value of energy efficiency than previously when only produce electricity about 40 percent, with a co-product such as by technology CHP (Combined Heat and Power) or CCHP (Combined Cooling Heating and Power), would be more than 2 times the efficiency of the original 80-sd typically around 85% of them. So, that conservation, this technology will be better.Industrial and commercial buildings usually require a source of energy in the form of steam heating or cold air from the results of this energy conversion. Survey on gas users illustrates that the tire production plants, food production and manufacturing in addition to requiring power also require steam as an energy source for production. Steam heat in the production process is not having high temperature of around 150oC with a pressure of approximately 7-8 bar so that the waste heat from the gas engine can be satisfied. While commercial buildings besides electricity also require air conditioning. Some commercial buildings surveyed have used air conditioning systems using waste heat as an energy source which is the output of the gas engine.The survey on producer gas engine is known that the gas engine has also been designed for low emissions that are environmentally friendly. In the example of the calculation of the gas engine to generate electricity alone and with gas prices today, it is less economical when compared to electrical systems that combine different types of power plants. But if the gas engine has been prepared to become a CHP or CCHP will be able to generate value for the lower cost of electricity existing tariff system.Overview on examples of problems CHP in PGN’s Office building at Bekasi to see economic studies using spreadsheets created show that for on the Project IRR of 21.88% and 99% capacity factor like the output price electricity prices amounted to 11.07 cents USD per kWh, cooling energy 32.8 cents USD per TRh with 13,500 rupiah exchange rate. Machine Capacity used is 8,450 kWh/day (Gas Engine) and 7,605 TRh/day. The gas consumption required is 3,726.45 m3/day (0,13 MMSCFD). The financial output is IRR 21.88 %, Engine Investment is USD 1.1 million, Payback period 5 year and NPV Project $ 660,147.

Supervisor: Tritjondro Baskoro