Efficiency and supply resource options for the upgrade of the Plzen district heating system

We examined options for meeting the district heating system steam and hot water heating loads associated with the Plzefi Central Heating Plant, two interconnected boilers serving the Kosutka and Bory regions, and the distributed systems in the Letna/Doubravka and Svetovar regions. The assessment applied integrated resource planning to combine the separate supply and demand-side assessments conducted for the system. Four system load scenarios were examined-high and low growth with and without programmatic efficiency. Hot water loads ranged from the current level of 277 megawatts thermal (MW{sub t}) to 320 MW{sub t} in a high growth scenario without efficiency to 253 MW{sub t} in a low growth scenario with programmatic efficiency. The high growth scenario includes an addition of approximately 50 MW{sub t} load from the connection of distributed boilers. An additional 250 MW{sub t} load served by distributed boilers may provide additional potential for system expansion. Steam loads are projected to increase from 93 MW{sub t} to 100 MW{sub t} in the high growth scenario and. decrease to 89 MW{sub t}, in the low growth scenario. Two system expansion cases were considered. The moderate system expansion provided for the Heat Line East I connection to serve the Letna/Doubravka region and the fall system expansion case further provided for the Heat Line East II connection to serve the Svetovar region. In the moderate case, the life of the Svetovar plant is extended to continue as a stand-alone system. Four central plant supply configurations providing for additional cogeneration capacity were applied to the load scenarios: 1. Life extension to existing facilities with a new coal-fired cogeneration unit in 2003, 2. Retirement of some existing units and a new coal-fired cogeneration unit in 1997, 3. Retirement of some existing units and a new gas- fired cogeneration unit in 1997, 4. Gas: Retirement of some exiting units a new gas-fired cogeneration unit in 1997