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Energy savings potential in the Hungarian public buildings for space heating
| Content Provider | Semantic Scholar |
|---|---|
| Author | Korytarova, Katarina Ürge-Vorsatz, Diana |
| Copyright Year | 2010 |
| Abstract | According to IPCC the largest amount of cost-effective mitigation potential is in the building sector. Most of the studies, however, focus on the residential sector, and only few on non-residential buildings. This paper describes the results of energy savings and mitigation potential analysis in the Hungarian public sector for space heating. The abatement options include improvement of energy efficiency of building envelope and heating system, heat controls and passive energy standard for new construction. The baseline energy use is based on the results of energy audits collected under UNDP/GEF project for municipal buildings. Energy savings potential is determined using two different approaches. According to the well-established component-based approach more than one third of the 2030 energy use can be reduced cost-effectively which is in line with other studies of this type. The rather new, performance-based analysis shows that 3 times higher total potential can be achieved by gradual phase-in of passive energy standard to both existing and new buildings. Based on this approach, several scenarios are constructed to analyze the impact of different rates of retrofit and performance levels on energy savings, mitigation potential and cost-effectiveness. The study shows that although the rate of retrofit is a significant factor for the total potential, it is even more important to what level of energy performance buildings are built or retrofitted. The study shows that if existing buildings are retrofitted at an accelerated rate only partially, the resulting potential will be only slightly higher than if buildings are retrofitted at natural rate of retrofit to passive energy standard. Introduction The impacts of the climate change can be already observed. In order to prevent further and irreversible changes in climate and environment, IPCC recommends to keep the global average surface temperature increase below 2oC relative to pre-industrial levels, which translates into 50-85% by 2050 compared to current (2000) levels [Box 3.10, 1]. This means that in the short term CO2 emissions should be reduced by 20-40% by 2020 relative to 1990 levels [Box 13.7, 2]. Therefore, several countries have committed to targets on reducing greenhouse gas emissions and targets on reducing energy consumption as one of the key emitters of CO2 emissions. The EU has made a commitment to avoid the dangerous climate change and limit the warming of the average surface temperature below 2oC compared to pre-industrial levels [3]. Within its climate-energy package the EU set a 20% reduction target for its energy consumption by 2020 compared to 1990 [4]. At the same time, energy resources are scarce and the energy prices are increasing due to instability in energy supply. Several countries invest into energy efficiency to improve the energy security for their economies. Moreover, energy efficiency not only decreases the energy costs for the end-users, but also provides several other non-financial co-benefits, such as improved indoor air quality and thermal comfort, increased productivity and other. Although the need for the required emission and energy reductions is large, there is a significant potential for reducing the energy in different sectors of the economy in cost-effective way. Buildings offer especially large potential at zero and negative costs [5]. The main aim of the presented research is to determine the energy savings potential in the public buildings in Hungary. Among the research objectives is to find the optimal pathway towards lowEnergy savings potential in the Hungarian public buildings for space heating energy, low-carbon economy and to provide insights into the risk of the lock-in effect when buildings are retrofitted to suboptimal level. The structure of the paper is following: first, the energy savings potential is shown from two different perspectives, and then the results of the scenario analysis, including the lock-in effect is discussed. Determination of energy savings potential by two approaches Most of the reviewed studies focusing on building sector use bottom-up modeling framework (for example [6, 7, 8, 9, 10,11]. These studies rely on the component-based approach which calculates the total energy savings potential based on the potentials of the improved individual building components. Although this approach is by now well-established in the area, it is often criticized for not considering energy savings potential from the holistic point of view. Holistic point of view means that all systems in the building are considered together, result of which is that the building as a whole is treated as a system itself. This can be done through integrated design “a process in which all of the design variables that affect one another are considered together and resolved in an optimal fashion” (Lewis 2004 cited in 12). A holistically-oriented alternative is performance-based approach, which has been already used in building codes in several countries and is increasingly popular – several countries have published their plans to implement some performance based building standards in the future. [13, 14] have calculated the energy savings that can be achieved by applying these performance standards in several countries by using a simple performance-based model for new buildings. The current study uses bottom-up modeling framework with both component-based and performance-based approach for both existing and new buildings. While the component-based approach looks at the energy savings achieved by the individual building components, the performance-based approach considers the building as a whole. The componentbased approach shows the cost-effectiveness of the individual measures. On the other hand, the performance-based model determines the potential on the basis of the energy performance of the building and compares cost-effectiveness in different building types. Both approaches use the same building stock projections, building typology and specific heating energy requirements for the existing buildings (built until 1990). Hungarian public buildings are divided into eight main building types based on their function and size: small educational buildings (kindergartens and nurseries), large educational buildings (primary, secondary and tertiary educational buildings), small health care buildings (doctor’s offices and ambulance stations), large health care buildings (hospitals, medical centers etc.), small and large public administration buildings, social buildings (homes for elderly, orphanages), cultural buildings (museums, community centers). The building stock for year 2005 is based on publications and online database of the Hungarian Central Statistical Office [15, 16]. The future building stock is projected based on relevant historical indicators which vary by subsector, and are usually linked to the population. Among the indicators are number of children in kindergarten per 1000 inhabitants, students in primary, secondary and tertiary education per 1000 inhabitants, number of beds in hospitals per 10,000 inhabitants etc. The building typology is based on the observation of the buildings listed in the energy audits (see below), and the average floor area per building type. The specific heating energy requirements are based on a sample of energy audits collected from UNDP/GEF municipality project [17] and other sets of audits [18, 19]. The analysis of the energy audits shows that in general the large, multi-storey buildings use less energy than the small, onestorey buildings (Figure 1). This is in line with the premise that compact buildings (buildings with low A/V ratio) have a better energy performance. This premise, however does not hold for small and large health care buildings – high average daily temperatures and long working hours offset the low (suitable) A/V ratio in the large buildings (hospitals), and the large (unsuitable) A/V ratio in the small health care buildings (doctor’s offices, ambulance stations) offsets the relatively low temperatures and shorter working hours. Energy savings potential in the Hungarian public buildings for space heating Figure 1 Specific energy requirements of the Hungarian public buildings (kWh/m.a) Specific energy requirements of Hungarian public buildings (kWh/m.a) 0 50 100 150 200 250 300 350 400 Kindergartens Primary & secondary schools Doctor's offices Hospitals & medical centres Small public administration Large public administration Social buildings Cultural buildings kWh/m.a "Other" Water heating Space heating Source: UNDP/Energy centre (2008), Nagy (2008), Csoknyai (2008) Note: ‘Other’ includes mainly lighting and appliances. The most energy intensive are social care buildings (homes for elderly, orphanages) due to their high temperatures and day-long working hours. The most efficient in terms of space heating are public administration buildings followed by the large educational buildings, mainly because of the building compactness and shorter working hours. Based on this common basic framework the business-as-usual (BAU) and mitigation scenarios are constructed under each approach. Component-based approach The BAU scenario in the component-based approach is based on the assumption that the considered energy savings measures are applied at natural rate of retrofit [1% p.a., based on 20, 21]. These include improving building envelope and replacement of the old boiler by a standard boiler (based on [10], [22] and product catalogues [23]). In the mitigation scenario all existing public buildings are assumed to be retrofitted by 2030. In addition to the BAU measures, temperature management is included and the old boiler is replaced by a more efficient, condensing boiler. New buildings are assumed to become passive by 2020 and this part of the model is the same as in the performancebased model. The component-based approach works on the basis of cost curve method. The advantage of th |
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| Alternate Webpage(s) | https://archive.ceu.edu/sites/default/files/publications/korytarovaurgevorsatz2010ieecbenergysavingspotentialinthehungarianpublicbuildingsforspaceheating.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
