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Heating PowerPoint Presentation

Heating

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Heating

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  1. Heating Martinás Katalin ELTE, Atomfizikai Tanszék

  2. Exergy and Industrial Ecology • Case study – District heating

  3. District Heating and Cooling?Market Failor • EU – good – the future Or • Hungary – uneconomic – the past • MARKET FORCES TO LEAVE THE DH SYSTEM

  4. HEAT PUMP 1,5 WOOD 2,5 COAL 3,1 GAS 3,6 DH 4,5 ELECTRIC 6,0 PB-GAS 7,1 Prices Ft/MJ

  5. The four laws of thermodynamics • 0.  Bodies in contact with each other assume the same temperature. • 1. energy conservation • 2. Any transformation leads to losses • 3. When the temperature of a system is zero (K) entropy reaches a constant value.

  6. Heat pump • 1 GJ heat • -3 C environment • 27 C room 1* 30/300 = 0,1 GJ electric energy

  7. Exergy • Exergy is a term that is used to show the maximum work a system can produce

  8. Exergy • All the differences: • B = (T-To)S – (p -po)V +… • Thermal part • B = Q (T – To)/T

  9. Laws of Nature • Exergy – no production • Every transformation leads to losses

  10. Exergy of heating1 GJ Heat Inside outside B temperature temperature 20 20 0 20 10 0,03 20 0 0,06 20 -10 0,1

  11. Exergy of with gas heating1 GJ Heat Inside outside Exergy temperature temperature loss 20 10 0,97 20 0 0,94 20 -10 0,9

  12. Solution - cogeneration All energy end up as heat

  13. Cogeneration • Present practice • 50% less fuel for heating

  14. Exergy price comparision PRICE Exergy Ex-price • Ft/MJMJ/MJ Ft/MJ • HEAT PUMP 1,5 0,9 1,7 • WOOD 2,5 1,7 1,5 • COAL 3,1 1,4 2,3 • GAS 3,6 1,2 2,6 • DH 4,5 0,6 7,5 • ELECTRIC 6,0 3,0 2,0 • PB-GAS 7,1 1,2 5,1

  15. Advantage of DH • Can utilize energy with low value (exergy) - utilize loses from many other processes (CHP, waste incineration)‏ • Easy to change fuel – few units • Easy flue gas cleaning – few units • Big share of cost are investment cost – steady prices, money stay in the local community

  16. Hungary • Főtáv Zrt – 2007- 12 Md GJ • 4500 Ft/GJ Energy – from gas – 8,5 Md Ft from PP – 23,8 Md Ft electricity- 1,3 Md Ft wages 2,2 Md Ft other 17,8 Md Ft

  17. Győrhő Zrt- • 2790 Ft/GJ • In Győr DH is cheaper than the gas heating.