Annual Report Department

2.9Energy and environment

2.9.1Impact of energy saving measures, cogeneration and fluctuating renewable sources on the greenhouse gas emissions by means of MARKAL

This research aims at studying the implications of the Kyoto Protocol for the Belgian energy situation. In this Kyoto Protocol context, Belgium has committed itself to a CO₂-eq emission reduc­tion by 7.5% in the period 2008-2012, compared to 1990. Starting from this commitment as a given, possible technical abatement options and policy measures to realise this emission reduction have been charted and assessed. The most important energy saving options and energy supply technologies are introduced in MARKAL, a long-term, multi-period energy technology model. This model incorporates a technological description of the main energy transfor­mation and energy use processes per sector of activity in the Belgian energy system, thereby including the possibility of technological learning. This way, these options are compared as to their effectiveness in properly reducing green­house gas emissions. Different scenarios are simulated so that the influence of various parameters, both technical and economical, can be examined.

This research has the objective to provide a useful tool for helping to orient future greenhouse gas policies, by considering energetic-technical, economic as well as ecological aspects. Special attention is given to the study of the energetic and ecological impact of implementation of cogeneration and fluctuating renewable sources in the Belgian energy system. These results are compared with simulations obtained with the software tool PROMIX.

Related projects: K.U.Leuven Energy Foundation Industry-University: Kyoto and the reduction of greenhouse gas emissions.

Scientific staff: W. D’haeseleer, M. Gysen, P. Luickx

2.9.2Energetic and ecological impact of massive implementation of cogeneration in Belgium versus neighbouring countries

In order to estimate the primary energy savings of massive implementation of cogeneration, several static formulae have been developed such as the so-called quality index. These static formulae are not capable, however, to incorporate the dynamic interaction of the cogeneration with the central electricity generation system. Therefore, in this research, simulations are performed. Two types of situations are fully simu­lated and quantified. In one case, no cogeneration is implemented. All power is generated by the power system and the heat is delivered by furnaces. In the other case, cogeneration is (partially) implemented in the same energetic context, leaving the final total demand for heat and electricity unchanged. The comparison of both situations answers the question about the energetic and environmental impact of that specific kind of cogeneration. To accurately perform the simulations of electricity generation, the software tool PROMIX is used.

It seems to be borne out that the static evaluation methods are only valid for very specific cases where the use of the considered cogeneration is fairly constant throughout the year. Indeed, in this case dynamic considerations become less relevant. In other cases (e.g., cogeneration for residential heating) the static formulae seem to overestimate the potential reduction in energy use or greenhouse-gas emissions. A major effort is being undertaken to validate the earlier obtained PROMIX results for Belgium with the code MARKAL. Furthermore, PROMIX has been adapted for the neighbouring countries France, Germany and the Netherlands and simulations are being performed to check how the generation mix in those countries influences the CO₂-emis­sions due to massive introduction of cogeneration.

Related projects: K.U. Leuven OT project OT/99/16: The influence of the Kyoto protocol on the generation mix for electricity in the EU in the context of liberalisation of the electricity market; FWO project: Influence of the “flexible mechanisms” for CO₂ reduction and of the liberalisation of the electricity market on the European generation mix for electricity; K.U. Leuven Energy Foundation Industry-University: Kyoto and the reduction of greenhouse gas emissions; bilateral project with Electrabel: Experimental system analysis of a mini-fuel cell in CHP mode.

Publications and reports: 2003P13, 2003P55, 2003P60

Scientific staff: W. D'haeseleer , K. Voorspools, M. Gysen, I. Peersman

2.9.3Analysis of thermal systems for extremely low energy dwellings

Nowadays one aspires to design domestic dwellings with such low thermal losses that one has to use only a limited amount of external energy for spatial heating and sanitary warm water production. This research project concentrates mainly on the energetic interaction between the building and the thermal installation(s) to ensure a “comfortable” temperature. This encompasses both heating, avoidance of overheating or ensuring cooling. Especially aspects related to thermal inertia, correct dimensioning of the installations, appropriate temperatures in the different living, sleeping and other rooms during all seasons are of importance. The following technologies will be considered for thermal installations: condensation boiler, co-generation (based on gas engines, fuel cells or Stirling cycli), heat pump, electrical heating, conventional thermal storage tanks or electrical boilers, solar collectors, etc. The control aspects of the entire system will prove crucial to obtain an efficient solution.

Related projects: IWT-GBOU-project: EL²EP Residential Buildings

Scientific staff: W. D’haeseleer, L. Helsen, L. Peeters

2.9.4Greenhouse-gas emissions due to electricity generation and the effect of the liberalisa­tion of the European electricity market

A-priori "linear" estimates concerning the greenhouse-gas emissions due to electricity generation not always appear to be justified. Therefore the electric system, to which the measure is applied, can best be simulated; both for demand and supply side measures. Two codes have been developed for this purpose: PROMIX and E-SIMULATE. By means of these simulation tools, different scenarios have been compared, and policy recommendations have been made. PROMIX has specifically been designed for the simulation of electricity generation in one region. PROMIX has been used extensively to accurately determine the impact of, e.g., the massive introduction of cogeneration and the prohibition or promotion of electric heating and to quantify the emissions of scenarios for the near future in scope of the emission constraints imposed by the Kyoto protocol.

E-SIMULATE has been developed to add the dimension of trade between regions. E-SIMULATE simulates power generation and trade in electric energy in different interconnected zones.

Until a few years ago, supply of electricity occurred in a regulated context. In the near future, all customers will be “free” to choose their supplier. The consequence is that utilities act with a very short-term perspective as far as investments are concerned. Cost cutting is the rule. In addition, the trading game is being driven by economical forces, whereby the technical constraints of electricity are often disregarded. As a consequence, some conflicts between the technical and economic points of view arise.

Presently, work is proceeding on the mutual influence of the liberalisation of the electricity market and the constraints imposed by the Kyoto protocol on the reduction of greenhouse gasses (taking into account the allowed flexibility mechanisms). PROMIX and E-SIMULATE can be used on a European level to simulate different scenarios in the context of the liberalisation and GHG limitations.

Related projects: K.U.Leuven OT project OT/99/16: The influence of the Kyoto protocol on the generation mix for electricity in the EU in the context of liberalisation of the electricity market; FWO project: Influence of the “flexible mechanisms” for CO₂ reduction and of the liberalisation of the electricity market on the European generation mix for electricity.

Publications and reports: 2003P17

Scientific staff: W. D'haeseleer , K. Voorspools

2.9.5Cost/benefit analysis of mitigation-possibilities to reduce the costs of damage due to voltage sags (brown-outs)

Some electrical applications, such as motors with variable speed drives, are sensitive for a brief drop in the electrical supply voltage (also called voltage sag or brown-out). If these applications are integrated in an industrial process, such a brown-out causes a process interruption with considerable financial damage. Solutions to prevent these damages are commercially available. These include solutions in the process itself, installing mitigation equipment such as an Uninterruptible Power Supplies or changes in the electrical supply network. These solutions are often very expensive. To choose the best possible solution requires a thorough study of the situation. The aim of our research is to calculate an economical optimum between the cost of the brown-outs and the mitigation costs. This is done by investigating industries in the same line of business in order to draw general conclusions.

Related projects: Bilateral project with ELECTRABEL: Cost/Benefit analysis of mitigation-possibilities to reduce the costs of damage due to voltage sags (brownouts).

Publications and reports: 2003P06, 2003P26, 2003P33, 2003P34

Scientific staff: M. Didden, R. Belmans, W. D'haeseleer

2.9.6Energy savings, Demand Side Management in an open electricity market; the cost of a saved kWh

Rational Use of Energy (RUE) is standing in the spotlight due to the world-wide concern of Global Warming. The aim of the research in this area is to examine the policy framework of RUE in the regulated market and to identify the possibilities in the future liberalised market. In the seventies, electricity companies in de USA were obliged to plan their activities according to a new concept, called Integrated Resource Planning (IRP). With IRP, electricity companies are forced to investigate whether there are less costly options to reduce the amount of consumed electricity. These actions, such as giving information or rebates on efficient applications are called Demand Side Management (DSM). With the liberalisation of the electricity market it is doubtful that an IRP-process can be maintained. Our research finds that IRP cannot be upheld in an open electricity market. But, there are good alternatives, however. Although it seems to be paradoxical at first, it can be concluded that national governments have a key guiding role in order to make these alternatives work. We have identified which actions the Belgian government has to take to uphold DSM in an open electricity market and we have also evaluated the role of other actors such as the electricity business itself. In addition, our work critically evaluates the energy-savings claims found in the literature; furthermore, we try to acquire a thorough understanding of the cost of a saved kWh.

Scientific staff: W. D’haeseleer, M. Didden, G. Van den Branden
Publications and reports: 2003P12, 2003P53, 2003R02

2.9.7Technical-economically integrated model of energy supply by hydrogen

The aim of this research is to develop a technical-economic model of energy supply by hydrogen and to get insight in the feasibility of a future hydrogen energy economy in by evaluation and optimisation. The model starts with a regional, closed approach (embedded generation), but couples with surrounding energy economies on national, European and worldwide level to allow energy flows (in and out) and to take international price evolutions of all energy carriers into account. Production, transport and storage of hydrogen are studied thoroughly and compared with competitive carriers such as electricity and natural gas. All identifiable, but useful, potential production ways are incorporated. The integrated character of the model is important: e.g., environmental concerns necessitate to take CO₂ capture and storage into account, when producing hydrogen out of fossil fuels; the transportation sector could influence the breakthrough of a hydrogen economy strongly. This research aims to define the interactions of this globally-integrated system on energetic-technical, economic and ecological level and to draw the right conclusions, a stable energy supply being a boundary condition at any time.

Related projects: IWT – GBOU project: Embedded generation: A global approach to energy balance and grid power quality and security.

Scientific staff: W. D’haeseleer, D. Haeseldonckx