Browsing by Subject "Combined heat and power"

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    A Biomass Fuel Assessment for Duke University’s Chilled Water Plant #2
    (2010-04-30T15:51:51Z) Crowley, Richard
    This Masters Project identifies the University’s biomass fuelshed and locates potential supply sources and probable fuel quantities. An Excel workbook couples user-defined transportation, processing, collection and handling, and purchase premium expenses within fuel classes to establish probable purchase costs for each supply source. Results are optimized for a lowest cost fuel mix to meet modeled plant demand based on user defined plant parameters. Finally, total biomass fuel costs are compared to fossil options to determine if biomass is a financially justifiable fuel for Duke to pursue. The results of this study indicate that the university fuelshed likely contains supply for more than 4 times the steam plants fuel requirements. The cost per million British thermal units combusted within the fuelshed is highly variable, ranging from approximately $1.01 for construction / demolition material to over $29 for forest thinnings. Several fuel classes are more economic than current prices for natural gas, ranging from less than a quarter to three quarters of the price of natural gas. The preliminary assessments of purchasing biomass fuel for use in the plant resulted in costs significantly lower than natural gas, and even potentially lower than coal. It is anticipated that the annual fuel costs for a biomass plant could be met for around $2.25 million based on plant parameters modeled and the estimated biomass characteristics (collection, base cost, etc.). Fuel costs are demonstrated to be highly sensitive to changes in fuel properties (mainly distance and moisture content) and plant operating parameters. A large portion of the biomass estimates are derived using employee based proxy equations, and the author was unable to confirm the accuracy of these supply estimates. Finally, the cost modeled is for fuel supply only. This paper does not take into consideration storage, operating / maintenance, or capital outlay, all of which are traditionally higher for biomass than fossil fuels. Despite these uncertainties there is a clearly demonstrated opportunity to fuel the plant with biomass at a cost less than natural gas. Additionally, the large and diverse biomass supply will lend resiliency to market fluctuations.
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    The Combined Heat and Power Market for Small Commercial End-Users in North Carolina
    (2007-12-05T20:38:43Z) Papalia, Edward
    Combined heat and power (CHP) is an approach to generating both electricity and usable thermal energy than can offer numerous environmental and economic benefits over more conventional generation methods. Previous research has made clear that the technical potential for additional CHP is huge, yet questions still remain as to how much of this potential is actually economical, and therefore likely to be adopted by end-users. This report evaluates the economic potential for CHP in the commercial and institutional sectors of North Carolina, with a focus on the relatively small (<1 MW average electric demand) end-users. Using prevailing and projected energy prices and equipment costs for CHP units commercially available in 2007, the likely returns on investment were assessed for the purchase of reciprocating engine CHP systems ranging from 100 kilowatts (kW) to 1,000 kW in capacity. The effect of various financial incentives on investment returns, including rebates and long term, low interest rate loans, was also evaluated. This assessment finds that given prevailing and projected energy prices, CHP at present would not be an attractive investment for most commercial sector facilities in North Carolina. Facilities that require an uninterrupted source of power, or that are capable of producing their own source of fuel, are likely exceptions, and could potentially benefit economically from CHP even given the state’s relatively low spark spread. While various incentives and low interest loans could significantly improve the economics of CHP for much of the sector, the financial outlay required to do so would likely be on an order of magnitude not currently seen in any state. Taken together, these findings suggest that CHP will likely play a limited role in meeting the state’s energy needs, at least for the foreseeable future.