COMMERCIAL AND INDUSTRIAL ON-SITE ELECTRICAL POWER GENERATION Today there is a feasible and very cost effective alternative to being dependent on the utility power supplier. Independent on-site electrical power generation is emerging as a viable cost-effective option for the industrial power user. Using on-site generators is not all that different from using the power from the utility company, but the one major difference is control. Power companies use remotely located generators to make power, but their generators are larger and they have to use a power distribution grid to get the power to the user. On-site electrical power generation involves using a generator or series of generators to meet all or part of industrial facilities power requirements. For many years now, on-site electrical generators have been widely used to produce emergency standby power. Today's advanced electrical generation equipment uses proven technology to provide electrical power that is reliable, safe, stable, efficient and environmentally friendly in many cases at a fraction of the cost of purchasing electricity from utility companies. GENERATOR SYSTEM TYPES There are four basic types of generators used for on-site electrical power generation systems: Generator systems that provide all the electrical power requirements of a facility that is completely independent from the utility grid. Generator systems that provide emergency standby power if the utility grid fails. Generator systems that "peak shave". This type of system is also referred to as base load displacement and it utilizes sophisticated switch gear to operate in parallel with the utility company power grid. Peak shaving generator systems supply the bulk of an industrial facilities electrical load during peak load and rate periods. Hybrid synchronous-induction generator systems. This type of system also utilizes sophisticated switch gear to allow for peak shaving, island mode and backup in the event of utility company power outages. This is also referred to as a split-system. NATURAL GAS POWERED GENERATORS Natural gas powered generators easily meet local and state air quality permit standards for prime power (continuous) power generation applications. Natural gas generators cost more than 100% diesel or dual fuel generators. The kW ceiling size for 100% natural gas spark ignited engines is about 1 megawatt at a cost of about $1,000,000 installed, with cogeneration equipment and switch gear. In California natural gas generators and turbines are the only fossil fuel systems that qualify for the 30% rebate programs. DUAL FUEL ENGINES Dual fuel engines are modified diesel engines. Diesel engines converted to dual fuel de-rate about 20% when running on a mixture of natural gas and diesel. Dual fuel generators use 5 to 30 % diesel for a pilot fuel in the pistons to create ignition. The advantage to the dual fuel engine is it accommodates larger kW units in natural gas at a lower price than a 100% natural gas generator. The dual fuel engine can meet air quality standards in many states. Modified dual fuel diesel engines can go as high as 2.5 MW. Dual fuel generators are more expensive than their 100% diesel counterparts. The dual fuel conversion equipment adds additional $320,000 to the cost of a 2.5 Megawatt generator system. DIESEL GENERATORS Diesel generators can go as high as 6 MW per unit. The 100% diesel is the most cost efficient option. A 2.5 Megawatt 100% diesel generator costs about $ 950,000. Smaller sizes are also available. SOLAR ELECTRIC SYSTEMS Solar electric systems are the most expensive option in terms of initial capital expense. They also are limited to providing power during peak daylight hours. The advantages to solar electric are that they have no fuel costs and very little maintenance expense. Also solar electric systems in California qualify for a 50% rebate program. Solar electric systems are particularly applicable to peak shaving applications. High peak demand electrical rates coincide with the time of the day that solar electric systems produce maximum output. Solar electric systems work especially well with commercial application where there is a large flat roof to mount the solar panels onto. There is one area in Southern California that has overlapping rebate programs. This area is serviced by both Los Angeles Department of Water and Power (electric) and Southern California Edison (Gas). If you live in this area you can receive up to an 80% rebate on a solar electric system. A solar electric system can cost up to $7,000,000 a megawatt, but if we look at the high rebate program, the absence of a fuel cost, minimal maintenance cost and no air quality permits, solar electric has feasibility in some applications. ELECTRICAL LOADS AND GENERATOR SIZING Generators need to be properly sized. One important factor in properly sizing a generator system is determining surge loads. Peak load demands occur when large electrical motors are in the process of starting up. When electrical motors start they can draw a momentary surge demand that is five times larger than their normal operating demand. Load scheduling is one way to control peak load demands. Many times motor controls can be installed to insure that multiple electrical motors are not starting at the same time. The other important factor to consider in sizing a generator system is the fact that generators achieve their best fuel economy and least engine wear when operating at a load range of 70% to 80%. COGENERATION The added benefit of on-site electrical power generation is the potential for co-generation. Co-generation involves utilizing the heat that is normally wasted to meet all or part of the thermal requirements of heating or air conditioning. One of the most common applications involves collecting waste heat from the generator exhaust gases and diverting it to an absorption chiller for cooling and air conditioning. This further adds to the feasibility and cost efficiency of on-site electrical power generation. "PRIME POWER" VERSUS "STAND-BY POWER" The other consideration is "prime power" versus "stand-by power" generation. Each generator has a "prime power" versus "stand-by power" rating. A "prime power" rating indicates how much power the system can generate continuously, 24 hours a day seven days a week. A "stand-by " rating indicates how much power the system can generate during a short spurt. The "stand-by " ratings for an engine are always higher than its "prime power" rating. It is important to understand this when comparing apples with apples. Many times a generator will be advertised based on its " stand-by " rating. Emission Controls Another consideration is emission controls. The 100% natural gas engine is going to be the easiest and most cost efficient machine to make compliant with rigid emission control standards. The next most cost efficient option is the dual fuel engine and the last in line is the 100% diesel engine. The 100% diesel engine can meet stringent emission control standards with the use of expensive catalytic converters. GENERATOR FUEL OPTIONS Natural gas is one of the most common fuels used for the onsite generation of electrical power. Natural gas has the advantages of being clean-burning and universally available in metropolitan areas. For larger electrical generation units, combination fuel generators are another option. Combination fuel generators run on a mix of 95% natural gas and 5% diesel. The advantage to this systems is that it is less expensive that a 100% natural gas system, it meets most clean burning environmental standards and it has the capability of running on 100% diesel. In the event that a disruption occurs in the supply of natural gas, having the ability to switch over to 100% diesel fuel insures continued power generation capability. Diesel powered generators are another option. Diesel is the most cost-effective option, but it does require on site fuel storage and truck delivery. Diesel emissions are not as environmentally friendly, but in most cases pollution control devices can be added to meet local emission control standards. Fuel availability, price and storage constraints are additional consideration factors. System Packaging Generator systems can come either skid mounted or containerized, depending on your needs and applications. Containerized units offer both increased sound attenuation and weather proofing. OTHER CONSIDERATIONS Be aware that large electrical motors can demand three to five times there normal operating current during start-up (locked rotor phase). A 1 kW electrical motor may require a 3 to 5 kW generator to start the motor. Many times, where there are multiple electrical motors in a system, it is advisable to install timer controls that insure that all the motors are not starting at once. Starting motors in series, one at a time, eliminates a huge locked rotor demand at start-up. Such a demand can overwhelm the capacity of the generator. Also be aware that transfer switches are required for back-up applications.

RESIDENTIAL POWER GENERATION   THIS PAGE UNDER CONSTRUCTION