Distributed Energy Systems
Distributed Energy Systems
The Competition for Small, Self-sufficient, Energy Systems
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The CEC approach appears to be a highly competitive, next generation energy system capable of taking the evolution of CEC power into distributed energy systems a long way by cutting energy costs for whole communities of small to medium businesses and family residences and at the same time reducing air pollution very significantly. Gas TurbinesInternal Combustion Gas TurbinesConventional gas turbines are suitable for larger industrial cogeneration applications and in combined cycle power plants. The new breed of micro turbines apply well to smaller industrial and larger commercial uses. However, all open cycle gas turbines are most efficient under steady, full load conditions and lose their competitive edge when they have to cope with part load operation for much of the time. To maintain high part load efficiencies, a gas turbine has to provide for control of the density of the working fluid in its cycle. That requires a closed loop, external combustion system. External Combustion Gas TurbinesOther than its own, the Company knows of no closed loop, external combustion gas turbine system aimed at commercial energy applications at this time. A common challenge facing all small energy systems is the achievement of high operating efficiencies at low cost. The CEC system design establishes breakthrough standards in simplicity, low cost, reliability and performance for systems under 60 kilowatts capacity.Solar SystemsPhotovoltaic systems pose peripheral competition, since they function only when there is sunlight and generally lack the power density to meet the requirements of commercial businesses on their own. While there have been evolutionary improvements in their costs, photocell systems remain expensive relative to existing energy approaches. The direct use of solar heat in energy systems is also expensive and is best used to augment the performance of elements within conventionally fueled systems. Fuel cellsThere are a number of fuel cell energy systems being promoted for relatively small applications, but so far they have not been cost competitive. The lure of fuel cell technology depends significantly on the expectation that fuel cells will be non-polluting. This is not universally true, since the problem of reforming fuel to create hydrogen has to be taken into account. Furthermore, in order to obtain high enough performance from PEM fuel cells, they need to be pressurized, and the turbo charger for that purpose is comparable in cost to the entire CEC turbo generator.Reciprocating EnginesInternal Combustion Cycles
Small generator sets with outputs in the range of 4 to 60 kilowatts are commonly used as emergency power sources in the market sectors of greatest interest to CEC. A review of U.S. dealer prices for most brands of generator set, both standby and continuous duty machines, yields the comparison curve below. The price per kilowatt of the CEC unit is very competitive, especially when considering the higher reliability and much greater endurance of turbo machinery as compared with reciprocating engines.
The Sterling Cycle provides for external combustion within a reciprocating engine configuration. Several companies were formed to produce and distribute Sterling cycle engines for commercial use. Natural gas fired units would make sense in the small to medium size commercial market if they could be produced cost effectively. Because they are most efficient at high input temperatures the Sterling cycle lends itself well to use with solar concentrators. However, concentrators take up too much space to be of material interest in the small commercial power market. The Company believes that the physical nature (high pressures & temperatures) of the cycle results in an engine mechanism that is inherently expensive to manufacture. Sterling engines also pose seal design difficulties which can add significantly to maintenance requirements. Cost of OwnershipAcquisition price is only part of the overall cost of ownership of an energy system and because of the acceleration and deceleration forces inherent in any reciprocating engine they are never as durable nor reliable as freely rotating turbine engines. As was made apparent when turbine engines surplanted reciprocating engines in aviation, turbine engines outlast reciprocating engines from one overhaul to the next by an order of magnitude, require far less maintenance, and are many times more reliable. Furthermore, the CEC unit offers the significant advantage of requiring no lubrication and very little scheduled maintenance. Hence, there is little doubt that it's design is much more affordable to own and operate than its reciprocating counterpart.Future TechnologiesTechnology advances in step with the expansion of knowledge and as human concern for the conservation of resources grows with population pressure the impetus for innovation in the energy field will continue to increase. Most of the advances will come from refinement and simplification of the mechanisms involved. In the realm of heat engines, materials are of great importance since they determine the performance of components under heat and load stresses. In this area, advances in the application of ceramics and other non-metallic substances will have a major influence. The high strength, low weight, configuration stability, and low thermal expansion of ceramics predestines this material for greater use with commensurate reductions in manufacturing costs. It is predictable that the use of ceramics in reciprocating engines will bring about performance and cost improvements similar to those achieved in gas turbines and other heat engines. The ultimate ceramic reciprocating power plant claims to have prospective properties such as:
These are clearly very long term, optimistic projections since manufacturers of high performance automotive engines are just beginning to adopt the use of ceramics in a few key areas such as valves, valve lifters, and valve seats, as Mercedes is doing experimentally for its C230 Kompressor 2.3 litre engine. The engineers estimate that ceramic valves could lead to a consumption improvement of between three and six per cent in a four-cylinder engine. By virtue of the physical complexity of a reciprocating internal combustion engine, progress toward the "ultimate" ceramic engine will inevitably be evolutionary process, whereas the substitution of a ceramic rotor assembly in a gas turbine is most naturally a one-step process. This is a significant advantage for the CEC turbo generator. Inaction and ComplacencyThe main resistance to the Company's market entry is that it departs from an entrenched business norm of simply turning on the switch to obtain electricity. This remains a comfortable notion until the price of power begins to undercut profits or rises to levels that provide strong incentives to find alternative solutions to gain a competitive edge. The thought of generating one's own power seldom occurs. The perception of technical complexity, substantial capital expenditure and fear of losing power militates against it. To overcome this reluctance, the CEC energy system is arranged around multiple turbo generators, very simple in configuration, requiring no scheduled maintenance at all. Each system is sized to carry the load even after the loss of one turbine so that an uninterrutible supply can be assured. Commercial systems will be leased rather than sold and the lease will include a comprehensive service agreement.
The key motivation is that it saves the
lessee virtually its entire monthly electricity bill. This is a compelling argument for commercial enterprises that spend more than their net income on electricity!
Historically, electric utilities have fought diligently to protect their rate bases and have charged customers that install their own generators substantial fees for backup power on the premise of having to maintain extra peak load reserves for such customers. This disincentive will prevail in spite of deregulation. For this reason, the Company's business model assumes complete independence from the utility, otherwise the money saved by its lessees will mostly disappear into the pockets of the power companies.
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The most commonly used engines in generator sets are four stroke internal combustion engines fueled either with diesel, gasoline, propane or natural gas. Except for engines based on the Diesel cycle, in which the heat of compression ignites the fuel, the engines based on the Otto cycle use more volatile fuels in conjunction with spark ignition.