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A TECHNOLOGY FOR TODAY Atlanta 2010
A TECHNOLOGY FOR TODAY
Atlanta 2010
Mechanical Systems Manager Smith College, Northampton, MA
Overview
Cogeneration Benefits
Technologies Case Studies
Why do Colleges have Physical Plants? Power Houses? Power Plant? Boiler House?
Hp Steam
LP Steam
IP Steam
Campus steam
Distribution
Power Plant
What about Electricity?
Conventional Power Generation
Conventional Power Generation
Typical Coal Plant Efficiency = 35% Best Modern Power Plant Efficiency = 56% Cogeneration Plant Efficiency = 65 – 85%
Cogeneration is the simultaneous production
of heat and electricity from one fuel source.
Cogeneration is not a new technology
Cogeneration Provides:
Onsite Generation of Reliable Power. Waste Heat Recovery for Heating, Cooling or Dehumidification.
Seamless System Integration.
Increased Efficiency of Energy Production and Distribution Systems.
Cogeneration Provides:
Renew Physical Infrastructure of Plant and Distribution. Reduce Exposure to Volatile Energy Markets.
Generate up to 90% of Annual Electric Needs of your Campus. Reduce Emissions - Especially CO2.
Very Efficient Multi Fuel Steam For Heating Electricity Steam for Cooling
Higher Efficiency = Lower Emissions
Any Questions or comments so far?
Cogeneration Technologies
Reciprocating Engines
Reciprocating Engines
Reciprocating Engines
Case Study - Wellesley College
Case Study - Wellesley College
Five Reciprocating Engines totaling 7.5 Mega Watts Export Excess Power to the Local Grid
Each Engine has it’s own HRSG
Each Engine has Jacket Cooling Providing Domestic Hot Water
Three Conventional Boilers Swing to Provide Thermal Demands
Reciprocating Engine Efficiency
Reciprocating engines have many desirable qualities: Quick Starts Follow Electrical Loads Well Multiple Engines in Battery High Electrical Efficiencies
Reciprocating engines are well suited to a variety of distributed generation applications
A few drawbacks: High Maintenance Low Exhaust Gas Temperatures Fairly High Emissions Usually Integrated with Boilers Vibration, Size, Noisy
Any Questions on Reciprocating Engines?
Boilers & Steam Turbines
Boilers &Steam Turbines
Boilers & Steam Turbines
Widely used in CHP Applications Oldest Prime Mover Technology
Capacities: 50 kW to Hundreds of MWs
Most Common Types
Back Pressure Steam Turbine Extraction - Condensing Steam Turbine
Boilers & Steam Turbines
Case Study - Williams College
Williams College One Boiler / Steam Turbine System
1 Nebraska Boiler – 70,000 lbs/hr @ 250 psi 1 Dresser Rand – 3 megawatt Back Pressure Turbine Two Conventional Boilers Swing to Provide Thermal Demands
Steam Turbines
Advantages: Simple Proven Technology Low Capital Cost No Frictional losses High Total Efficiency Disadvantages: Must Have a Boiler Long Start up Times Large Steam Demand Avoid Partial load Operation Avoid Starting and Stopping Constant Pressure and Temp
Advantages of Steam Turbines over
Reciprocating Engines Thermal Efficiency of a Steam Turbine is Higher than that of a Reciprocating Engine.
A Steam Turbine is a Much More Durable Prime Mover.
Much Higher Speed may be Developed and a Far Greater Range of Speed is Possible than in the Case of Reciprocating Engines.
No Real Frictional Losses in a Steam Turbine
Steam Turbines Come in a Very Wide Range of Sizes
Any Questions on Steam Turbines?
Combustion Turbines & HRSG’s
Compressor
Combustors
Turbine
Drive Gear
Heat Recovery Steam Generator
Combustion Turbines & HRSG’s
Combustion Turbines & HRSG’s
Case Study Smith College
One Combustion Turbine / HRSG Train
GT = 3.5 MW’s / HRSG = 20,000 lbs Steam per/hr Three Conventional Boilers Swing to Provide Thermal Load. (110,000+ lbs/hr)
No Steam Turbines. Steam goes Directly to Campus
Steam Provided for Chilled Water Production
Smith College Cogen
Amherst College Smith College
University of MA - Amherst
Dual Fuel Capability Incremental in Size Total Cycle Efficiency can be up to 80% Can Reduce Facility Energy Costs by Typically 30% Reliable on Site Electricity Generation Dramatically Reduce Campus Emissions more than any other Technology
Advantages of Combustion Turbine / HRSG Technology:
Some Disadvantages: High Initial Cost Pressurized Gas Required Sensitivity to Ambient Temperatures Long Term Service Contracts
• Produces Almost 8% of US Electric Power • Saves Colleges and Industry Owners Over $5 Billion/Year in Energy Costs • Decreases Energy use by Almost 1.3 Trillion BTU’s Per Year • Reduces NOx Emissions by 0.4 Million Tons Per Year • Reduces SO2 Emissions by over 0.9 Million Tons Per Year • Reduces CO@ by over 35 Million Metric Tons Per Year
Source (www.uschpa.org)
Cogeneration
Any Questions on Combustion Turbines and HRSG’s?
Do you pay more than $.07/ kilowatt-hours on average for electricity (including generation, transmission, and distribution)?
Are you concerned about the impact of current or future energy costs on your campus?
Is your facility located in a deregulated electricity market?
Are you concerned about power reliability?
Do you have thermal loads throughout the year (including steam, hot water, chilled water, hot air, etc.)?
Does your college have an existing central plant? Do you expect to replace, upgrade, or retrofit central plant equipment within the next 3-5 years?
Do you anticipate a facility expansion or new construction project within the next 3-5 years?
Have you already implemented energy efficiency measures and still have high energy costs?
Are you interested in reducing your facility's impact on the environment?
