12th International Symposium on District Heating and Cooling

heating market for district heating makes it moredifficult to expand:A rough rule of thumb has been that the expansion withnew customers that have been, (...), has been eaten upby the efficiency we could achieve together with thecustomers in their buildings. So basically, the heat loadhas been static in our area for quite some time. (…)…[The reason for building CHP] is the electricity. We,as the producing company, have the problem that wecan not expand. We have our two customers anddistrict heating is not a new thing in the municipalitiesso the chance of getting new customers is limited [22].The other representatives are of a similar opinion, thata stagnating load can be expected, and CHP is a wayto keep profits high. The Swedish certificate systemalso makes it advantageous to build new bio-fuelledCHP-plants. Another reason, arguably of a morerhetorical character, is that building CHP is moreeconomically and environmentally correct since the fuelefficiency is higher with CHPs. As scenarios 4–8 show,there is major potential for reducing local and globalCO 2 emissions.In the interviews we also asked questions about thepossibility of an introduction of natural gas in theregion. Investigations have been made earlier by theabove mentioned STOSEB; however, the plans nevercame to reality. Generally the representatives did notthink that an introduction would happen. Since most ofthem also have strategies to be climate neutral, naturalgas probably is not an option. The large investments ininfrastructure are another barrier:These are such large infrastructure investments andnatural gas is not especially cheap either. It is difficultto come in with natural gas in this energy system. It israther stable [23].What the representative here points at is also theinertia in the system. In LTS terms it is calledmomentum: as the system is stable, it is difficult tochange the structure [18], [19].6. CONCLUDING DISCUSSIONThe study has shown the advantages of aninterdisciplinary approach. Advantages withinterconnections and CHP have been shown in themodelling; however, as there are many different actorsinvolved, there is a need for a will to cooperate. Theinterconnections have a historical background, with anaim for higher supply security, and today most of themcontinue to cooperate, despite the fact that thestructure and ownership of the companies in somecases have changed since the deregulation of theelectricity market in 1996. As previous studies haveshown, the main advantages with cooperation havebeen economic, as is also the case in this system. TheThe <strong>12th</strong> <strong>International</strong> <strong>Symposium</strong> on District Heating and Cooling,September 5 th to September 7 th , 2010, Tallinn, Estonia294actors say that they can optimise the system'sperformance, and our scenarios have shown that morecooperation could benefit them even moreeconomically. Even though the gain is not extremelyhigh, since the lower system cost would beapproximately 5%, there is potential. However, sincethere seems to be reluctance to cooperate betweensome actors, it is difficult to fulfil the potential.Advantages with the cooperation are said to be apossibility to even out the production in the system andthus avoid peak load. The disadvantages with thecooperation are the need for more administrative workto control the system and the trades; the control of thesystem becomes more complex. This study alsoconfirms previous studies that have pointed out thattechnical aspects are seldom barriers to cooperation.Most things are solved while the systems are beinginterconnected, and the will of the persons involved tocooperate is important.There is a large potential in building new CHP plants,both from an economic and an environmentalperspective. If all the plants in the system werereplaced by BCHP or NGCHP, the electricity producedcould make up to 4.5 or 12% of total Swedish electricityproduction, based on the fact that total production inSweden in 2008 was 146 TWh [1]. The reason that thedifference between the electricity productions in thosetwo cases is so large is a big difference between theelectrical/thermal outputs (see Table V). The introductionof NGCHP is a less likely future since it can beconsidered only with the assumption that the naturalgas network already exists along the Swedish eastcost. On the other hand, introducing more BCHP in thedistrict heating system would increase the system‘sdependence on biomass availability and the heatproduction cost would become highly sensitive to thesolid biomass cost. The actors are highly aware of thepotential for CHPs. Since they are expecting astagnating heat load, the sale of electricity is a way tokeep profits high. However, none of them think thatnatural gas will become a reality in the near future, andeven if it did, the introduction is expected to besomewhat problematic, since the fuel can beconsidered fossil fuel and substantial infrastructure isneeded.The study has shown a potential for decreased LECO 2and GECO 2 . The largest potential from a localperspective is from BCHP; so, since the LECO 2 wouldbe low and with high electricity production, the potentialfor lower GECO 2 would exist. The high electricity-toheatoutput ratio in NGCHP has a high potential fordecreasing GECO 2 of the system. If all plants in thesystem would be replaced with NGCHP the GECO2 ofthe system would be -9 million tons annually. However,in that case LECO 2 would be much higher than today.