District heating networks can technically enable energy-related co-operations between energy-intensive industries and municipal energy companies. The most common form of co-operation is to utilise industrial waste heat as the primary energy source in district heating networks. However, another type of co-operation is to jointly own a plant that produces both process steam for the industry and hot water for district heating. In this article, eight Swedish energy co-operations are studied and the main focus is on the process leading to co-operations of this kind. Different aspects of factors that facilitate or obstruct the start up and continuous daily operation of a co-operation are discussed. The main conclusion is that while the primary reasons for the foundation of such co-operations are favourable techno-economic factors, this is not enough for a co-operation to emerge. This study highlights the importance of people with a real ambition to co-operate in both parties in the co-operations.

In the deregulated Nordic electricity market, countries have varying kinds of power generation. In Norway, hydropower generation dominates. while the Swedish electricity production largely consists of equal shares of hydro and nuclear power production. There is a larger share of fossil fuel power generation in Finland and, especially, in Denmark. Cross-border trade between the countries is considerable. Increased use of electricity anywhere in the region may thus entail augmented emissions of greenhouse gases. The amount of increased emissions due to additional electricity usage will depend on the type of generation supplying the additional electricity. Similarly, a decrease in electricity usage may involve reduced greenhouse gas emissions. In this paper. we discuss some different ways to account for changes in greenhouse gas emissions because of a changed use or supply of electricity. A comprehensive accounting scheme should provide an accurate link between various types of energy measures and their related emissions in order to facilitate cost-effective carbon dioxide mitigation procedures.

Methodologies to assess the effects of energy projects on global carbon dioxide emissions will be an important feature of a future international carbon dioxide trading system. In this paper, we present and discuss four different models for assessing the net carbon dioxide emissions resulting from a certain energy project. These models are applied to different district heating technologies. To judge the mitigation performance of a project, the amount of carbon dioxide released in kilograms is expressed per megawatt-hour of useful district heating produced. All the models consider the marginal change caused by the project on the electric power system. The different model perspectives are discussed, and it is shown that the choice of model is very critical for assessing the net carbon dioxide emissions from an energy project.

Carbon capture is often discussed in the literature with the sole focus on power processes, despite the fact that carbon dioxide emissions from other sources are just as relevant for the impact on the atmosphere. Furthermore, some carbon capture methods are relatively inefficient when applied to power production processes. Carbon capture should preferably be performed where the cost is as low as possible, i.e. not necessarily from power production processes. As an example, carbon capture using combustion with pure oxygen is far more energy efficient if it is used together with lime kilns or cement kilns than together with power production processes. A new concept termed "oxygen efficiency" is introduced in this paper. It describes the amount of carbon dioxide that can potentially be captured per unit of oxygen. As such, the oxygen efficiency quantifies the value of a certain unit of oxygen for carbon capture reasons. The base concept is that the energy penalty for the production of one part of oxygen is the same no matter where it is produced; hence, if this unit of oxygen can be used to capture more carbon dioxide, it is more efficient. Typically, the oxygen efficiency would be five times greater for carbon capture when utilising pure oxygen together with cement kilns rather than together with methane-fired power plants. Furthermore, the concept of oxygen efficiency illustrates the importance of considering how carbon capture methods can be utilised in the most efficient way, in addition to evaluating which carbon capture method is the most suitable for a particular technology.

Carbon dioxide capture and permanent storage (CCS) is one of the most frequently discussed technologies with the potential to mitigate climate change. The natural target for CCS has been the carbon dioxide (CO₂) emissions from fossil energy sources. However, CCS has also been suggested in combination with biomass during recent years. Given that the impact on the earth's radiative balance is the same whether CO₂ emissions of a fossil or a biomass origin are captured and stored away from the atmosphere, we argue that an equal reward should be given for the CCS, independent of the origin of the CO₂. The guidelines that provide assistance for the national greenhouse gas (GHG) accounting under the Kyoto Protocol have not considered CCS from biomass (biotic CCS) and it appears that it is not possible to receive emission credits for biotic CCS under the first commitment period of the Kyoto Protocol, i.e., 2008-2012. We argue that it would be unwise to exclude this GHG mitigation alternative from the competition with other GHG mitigation options. We also propose a feasible approach as to how emission credits for biotic CCS could be included within a future accounting framework.