Combined Heatand Power Application of a75-kW Microturbineat a Toronto Laboratory: Monitoring Results Brian BoydTechnology Directorate of PWGSC2001
Outline of presentation • Project Description • Equipment • Funding Partners • Site Description • Reason for Doing the Project • Project Chronology • Summary Figures • Conclusions
75 kW Microturbine CHP Application Project Description 2301 Midland Avenue, Scarborough has the first Canadian installation of a micro-turbine supplying electricity and waste heat to a building. The gas-fired unit was intended to operate continuously, providing 75 kW electric and 155 kW thermal heat. Natural gas consumption by the building’s boilers has been reduced by the application of recovered heat to space heating systems in winter and humidity control systems in summer.
Project Description 2301 Midland Avenue, Scarborough
Equipment Parallon 75 Honeywell International Inc.
Parallon 75 Honeywell International Inc.
Equipment • Parallon 75 • Honeywell Power Systems • Canadian Distributor: • Mercury Electric Calgary, AB • Features: • 75-kW gas-fired microturbine • No gearbox • A recuperator • Low NOx emissions in exhaust • Local support was provided by the local Honeywell group.
Equipment • MicoGen • Heat Recovery System • Unifin International, London, ON • This Canadian designed and fabricated heat recovery system increases the system’s overall efficiency by recovering the heat in the turbine’s exhaust and using it to heat hot water for space heating in the winter and humidity control in the summer. The heat supplied reduces the natural gas used in the building’s boilers.
Equipment • The MicoGen combined heat & power system reduces the need for design engineering, leaving only application and installation considerations. The heat supplied reduces the natural gas used in the building's boilers. • Further information on the equipment is available at the Unifin web site. • http://www.unifin.com/micogen.htm
Output During Operation: The building computer recorded the net outputs while various other parameters were logged by a computer connected to the turbine. The average measured electrical output of the turbine after it’s internal power needs are subtracted (such as fans and compressors) came to 68.4 kWduring the half year of its operation. Due to design problems the heat recovery system used only62.4 kWof waste heat on average. Honeywell International Inc.
75 kW Microturbine CHP Application Funding Partners • The costs of the installation were shared among: • PWGSC CAN$ 143 K • NRCan CAN$ 66 K • Enbridge Consumers Gas CAN$ 50 K • Kinectrics CAN$ 30 K • ( formerly Ontario Hydro Technologies ) • CAN$ 104 K of which went to the contractor, VESTAR. • CAN$ 77 K was the price of the turbine.
Cost Breakdown Source: NRCan
Assuming 110 kW heat recovery, this investment has less than a 1 year payback This is where the main cost reduction has to come Cost Breakdown Source: NRCan
Funding Partners The Technology Directorate of PWGSC originally obtained funding from the Program for Energy Research and Development (PERD) and later through the Technology Development & Transfer (TD&T) Program. The installation was done by VESTAR as a design-build through a contract with PWGSC, Technology (E. Morofsky, Project Manager).
Site Description Site selection: The building requirements were to be such as to continuously have a need for at least 155 kW heat and 75 kW electricity. The installation was to be monitored and evaluated for 18 months.
Site Description 2301 Midland Avenue, Scarborough
Site Description Building Host: Health Canada Laboratory Building @ 2301 Midland Avenue 3-story building approximate altitude of 600 ft. The building has also recently undergone a FBI (Federal Buildings Initiative) project that reduces its energy consumption by 50% through more efficient lighting, controls and a conversion of the constant volume ventilation to a variable volume system. (Retrofit done by Vestar, an energy services company supplying third party financing.)
Site Description The Building Operator: PWGSC - Ontario Region Rick Schveighardt Facility Manager Health Protection Branch - Health Canada 2301 Midland Avenue, Scarborough, ON M1P 4R7 Canada Tel: (416) 512-5667 E-mail:Rick.Schveighardt@PWGSC.GC.CA
Site Description Enclosure Heat Rec. Unit Concrete Pad Turbine Gas Meter Transformer Fuel H2O Sloped lines on water loop
Site Description Enclosure Concrete Pad Fuel Power
75 kW Microturbine CHP Application Reasons for doing the project Benefits of CHP (Combined Heat and Power) microturbines: - Reduction of greenhouse gas production - Potential energy cost savings - Versatility and stand-alone capability - Possibility of selling power back to grid
Reasons for doing the project Microturbines are used successfully in oilfields and it was suggested that they might be useful for providing supplementary or back-up power to buildings. The partners decided they wanted to gain experience in the field of turbine co-generation while exploring the feasibility of the suggested application. The Midland Rd. site is ideal since it is a lab and has a high power demand year-round, including a use for heated water.
Reasons for doing the project Source: PWGSC study All values in Canadian Funds
Project Objective CETC DISTRIBUTED GENERATION PROGRAM To obtain performance and operating experience with a Microturbine Combined Heat and Power system at the Health Canada Laboratory at 2301 Midland Road at high efficiency and low exhaust emissions compared to other fossil fuel generation power plants.
Project chronology: 2000 - 2001 • April 12, 2000 – Equipment Delivery (originally planned for September 30, 1999) • June 9, 2000 – Commissioned (originally planned for October 30, 1999) • November 7, 2000 – Unit shut down pending ETS Field Certification • June 9, 2000 - November 7, 2000 – Availability: 60% • Gas compressor and core replaced after 2000 hours of operation • January, 2001 – Monitoring Underway (originally planned for November 30, 1999) • January 4 – Emissions Testing • January 26 – A minor gas leak was detected by Enbridge and repaired by Honeywell. • February 5 – Versatech (mechanical contractor) replaced the bottom flange of gas meter and installed a flexible connector to the cogeneration unit. • February 6 – Vestar restarted the co-gen unit at 10:30 a.m. Logging was restarted at 12:00 noon (after 2614 hours of operation). • February 8 – Turbine stopped at 2 p.m.
Project chronology: 2001 • February 9 – Enbridge found the unit had been off for an unknown amount of time with the fault light lit. The key was turned from the normal position to the off position. • February 15 – Honeywell checked the unit and started it up at 1 p.m. • March 7 – Kinectrics turned the microturbine off briefly to install a power quality meter for a test. The power level was measured at 75kW. • March 14 – Honeywell performed a retrofit on the plenum sealing and fan hub upgrade. • March 27 – Honeywell fixed a leak on the outlet of the flex line to the ASCO solenoid and added 500ml of oil to the gas compressor, then got the unit up and running but it stopped at 4 p.m. • March 29 - Turbine restarted at 12 p.m. • April 6 – The computer was found off; the data may not be good. • April 6 – The computer was found off; the data may not be good. • April 23 – Honeywell attempted an efficiency test but the unit shut itself down after 8:30 a.m. and the test was delayed.
Project chronology: 2001 • April 24 – Honeywell suspects the shut-down is due to an ignitor which will be replaced. • May 9 – Honeywell installed the new ignitor and a new inlet air filter. The cooling module oil was found to be leaking and the unit was shut back down. • June 7 – Honeywell replaced the cooling module and the unit was running again by 4:00 p.m. • June 15 – Enbridge found the fault light flashing on the unit but it was left running until it switched off on its own at 8 a.m. • June 25 – Honeywell added 350ml of oil, checked for faults then switched the unit back on at 12 p.m. • June 28 – The fault light was flashing. • June 30 – At approximately 11 p.m. the gas meter’s first erratic reading is recorded. • July 6 – The fault light had switched off by itself. • July 11 – At approximately 11 p.m. the increasingly erratic gas meter stops reading gas flow altogether.
Project chronology: 2001 • July 18 – The unit switched of at 5 a.m. • July 20 – The unit was found off with the fault light on, and the unit would not restart. • July 24 – The unit is still off, the oil was topped up and the filters drained before restarting at 12 p.m. • July 27 – The Unit was running O.K. • August 9 – At start up, there was a flashing red light but no obvious fault. 500ml of oil was added. The filters were cleaned. Unit seemed to be running fine. The reclaimer damper linkage was disconnected and wired open. • August 15 – The unit switched itself off at 5 a.m. • August 17 – The unit was found off with the fault light steadily lit. • August 24 – The unit was still off and waiting to be serviced. • August 31 – The unit was checked but left off. • September 7 – The unit was still off. • Honeywell has since recalled all its microturbine units.
2001 Performance Summary • The microturbine logged 2939 hours in 2001 for a total of 5553 hours of operation at final shut down. • From the February power up until the August shut down the unit had an overall availability of 64.55 % • Typical values under steady running conditions : • natural gas consumption 1000 std.cubic feet / hour or 269.6 kW (LHV) • 26 % turbine efficiency @ ~70 kW power output • 30 % heat efficiency @ ~80 kW heat output • Overall averages: • power output: 68.4 kW • heat output: 62.4 kW • Inverter, transformer, and parasitic losses: 5 kW
2001 Performance Summary • Estimated Parasitic Losses: 1.4 -1.6 kW (fans, fuel compressor) • Thermal Performance: • Large thermal losses due to enclosure cooling air blowing over and through silencer system. • Good heat balance obtained around Unifin heat recovery system. The problem is the approach temperature is not the 250° C expected but 191 ° C • Likely fix will involve insulating duct from recuperator discharge; need to avoid restricting enclosure cooling flow which is significant • Average gas properties over test period: • HHV 1012.6 Btu/CuFt (0.2965 kWh/CuFt) • LHV 920.55 Btu/CuFt (0.2696 kWh/CuFt)
75 91 C Heat Balance 4th January 0°C Ambient ( all data in kW) STACK LOSSES to ambient temperature 191 C 37 LOSSES 70 84 POWER 75 HEAT 271 GAS
Performance Summary Preliminary Emission Results (g/kWh) Source: NRCan
Performance Summary Emission Data (dry ppm) Source: NRCan
75 kW Microturbine CHP Application Conclusions • The heat recovery was lower than expected (62.4 vs 155 kW) due to thermal losses on uninsulated parts of the recuperator and a reduced thermal output in winter. • The heating circuit design was a success using water instead of glycol in an outside freezing environment. • The noise issue, which had originally concerned the building operator, proved not to be a problem. • The emission data was found to be within specifications.
Conclusions The gas compressor caused problems because it was not registered with the local fuel safety organization and was noisy and unreliable. Is the installation economic and how many buildings are suitable for microturbine application? Many aspects of the installation at Midland Avenue would be done differently if we had a second chance. Most of these were due to inexperience with installing and operating a microturbine at a building site. We will be analyzing these issues and recommending standard installation procedures.
Conclusions The Health Canada Laboratory is not a typical building but other building types where clients require highly reliable power or dependable standby power with strict dehumidification requirements are potential applications. This would include laboratories, museums, computer facilities and 24/7 operations, and office buildings with alternate cooling needs.