Energy System Refurbishments – It Is a Long Way fromPilot Projects to Common Practice               Antti Kurvinen, M.Sc. ...
2Introduction and BackgroundA big number of different energy refurbishment pilot projects have been executed during thelas...
3phase on the basis of life-cycle costs and value factors. The final decision is made on the basisof total solutions’ affo...
4This methodology takes the limited financial resources as a driving constraint and assists theirallocation as effectively...
5To evaluate how the set energy saving objective could be achieved, alternative calculationswere prepared. The estimated e...
6       Selection of structural- and HVAC-technical                               Pay   Internal Choice       energy savin...
7                      Heating energy consumption before and after refurbishment                                          ...
8housing companies. The criteria is developed in the first phase of pilot case, and will be putinto practice in the second...
9ReferencesAalto, R & Heljo, J. 1984. Energy Saving Choices in Buildings (in Finnish). Helsinki,Rakentajain Kustannus Oy. ...
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Energy System Refurbishments – It Is a Long Way from Pilot Projects to Common Practice

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Authorities in many countries have set objectives for emission reduction, and energy consumption of buildings has an essential role in achieving those target levels. At the moment, a big part of Finnish building stock is facing refurbishment needs. To transform the existing building stock towards energy-efficiency, it is of importance that all economically profitable energy saving measures would be executed within the refurbishments actions. However, in many cases the full energy saving potential is not exploited in refurbishment projects.

During the last years, numerous pilot projects have shown how energy consumption can be remarkably decreased. However, even in the case of all pilot projects had succeeded, their accelerating impact on refurbishment projects’ energy-efficiency would not have been enough to decrease the energy consumption of the whole building stock level so much that the set emission saving objectives would be achieved. Such macro scale impact is our target. In addition to successful pilot projects, there have been also cases, in which the impacts have not been as positive as expected. Disappointments together with noticeably higher investment costs, as compared to basic solutions, slow down the popularity of energy saving refurbishments much more than good examples are able to accelerate it.

In such climate conditions as Finland achieving nearly zero-energy level in refurbishments is so expensive that it is hard to give economically profitable reasons for decision-making. Hence, it would be more beneficial option to concentrate on ensuring that as big part of the economically profitable energy saving measures as possible would be executed within refurbishments. If this opportunity is not used now, it will soon be too late.

Because investors will always require profitability for their investments, it is important to use systematic methodology in energy saving measure related decision-making. In this way the effective allocation of financial resources can be ensured and energy economically profitable measures will probably be executed.

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Energy System Refurbishments – It Is a Long Way from Pilot Projects to Common Practice

  1. 1. Energy System Refurbishments – It Is a Long Way fromPilot Projects to Common Practice Antti Kurvinen, M.Sc. (Tech.) , e-mail: antti.kurvinen@tut.fi Juhani Heljo, M.Sc. (Tech.), e-mail: juhani.heljo@tut.fi Jaakko Vihola, M.Sc. (Tech.), e-mail: jaakko.vihola@tut.fi Tampere University of Technology Faculty of Built Environment Construction Management and Economics FI 33101 TAMPERE, Finland www.tut.fi/eeAbstractAuthorities in many countries have set objectives for emission reduction, and energyconsumption of buildings has an essential role in achieving those target levels. At themoment, a big part of Finnish building stock is facing refurbishment needs. To transform theexisting building stock towards energy-efficiency, it is of importance that all economicallyprofitable energy saving measures would be executed within the refurbishments actions.However, in many cases the full energy saving potential is not exploited in refurbishmentprojects.During the last years, numerous pilot projects have shown how energy consumption can beremarkably decreased. However, even in the case of all pilot projects had succeeded, theiraccelerating impact on refurbishment projects’ energy-efficiency would not have been enoughto decrease the energy consumption of the whole building stock level so much that the setemission saving objectives would be achieved. Such macro scale impact is our target. Inaddition to successful pilot projects, there have been also cases, in which the impacts have notbeen as positive as expected. Disappointments together with noticeably higher investmentcosts, as compared to basic solutions, slow down the popularity of energy savingrefurbishments much more than good examples are able to accelerate it.In such climate conditions as Finland achieving nearly zero-energy level in refurbishments isso expensive that it is hard to give economically profitable reasons for decision-making.Hence, it would be more beneficial option to concentrate on ensuring that as big part of theeconomically profitable energy saving measures as possible would be executed withinrefurbishments. If this opportunity is not used now, it will soon be too late.Because investors will always require profitability for their investments, it is important to usesystematic methodology in energy saving measure related decision-making. In this way theeffective allocation of financial resources can be ensured and energy economically profitablemeasures will probably be executed.
  2. 2. 2Introduction and BackgroundA big number of different energy refurbishment pilot projects have been executed during thelast years. These pilot projects have an important role as source of practical data andexperiences applicable in other projects. However, when the main goal is to achieve aconsiderable decrease in energy consumption of buildings, executing pilot projects is notenough.The gained results so far are indicating that there is a long way from the current energyrefurbishment pilot projects to widely executed energy refurbishments which can haveimpacts of macro scale i.e. on building stock level (Heljo et al 2012). The outcomes andimpacts of these projects are not always as positive as expected. For instance, real energysavings may turn out to be lower than the calculated gains, which means lower economicprofitability. These kinds of negative pilot experiences can cause significant delays in puttingenergy refurbishments into practice: Real estate owners become more suspicious and carefulwhen making their investment decisions. This is a very unfortunate, but still understandablephenomenon. A simple and reliable decision making methodology is needed for improvingthe current situation. This methodology should be able to provide reliable data for decision-making and be able to describe energy saving measures’ effects in graphic detail.In the Finnish climate conditions achieving nearly zero energy level in refurbishments istroublesome. There are many reasons behind this problem. For example, cold winters,common fear of moisture effects caused by additional insulation and lack of economicreasons. Practice has shown that even all the economically profitable energy saving measuresare often not executed within refurbishment projects. Taking into account that in the Finnishclimate, refurbishments towards close to the zero energy level also require the use ofeconomically non-profitable energy saving measures, the challenge to overcome is evenbigger.A methodology to assist energy saving measure related decision-making is shortly presentedin this paper. Also one related pilot project will be presented. The focus is not only on theproject itself, but also on its affects on real estate owner’s common practices.MethodologyFinancial resources and their effective allocation have a very important role in decision-making. However, in many cases decisions in relation to the energy saving measures seem tobe made based on subjective feelings. This is naturally highly irrational, whereas the ultimatetarget should be decisions making practice based on real facts.A systematic decision-making methodology in relation to the energy saving measures ispresented in figure 1. In the first two phases, the basic solution of the refurbishment is usuallydefined on the basis of the structural and physical minimum requirements of the building. Thethird phase is to find out all reasonable system alternatives, e.g. for heat generation. In thefourth phase, profitability of energy saving measures in case of each system alternative(different energy cost) is studied. Profitability of energy saving measures is mainly estimatedon the basis of internal rate of return, but also value factors should be taken intoconsideration. System alternatives together with the profitable energy saving measures formalternative total solutions. Affordability of these alternative solutions is estimated in the next
  3. 3. 3phase on the basis of life-cycle costs and value factors. The final decision is made on the basisof total solutions’ affordability. 1. BASIC INFORMATION AND THE FACTORS AFFECTING THE CHOICES OTHER CONTROLLING FACTORS DEFINING THE NEED FOR NEW DEFINING THE BUILDING RESOURCES AVAILABLE RESOURCES AVAILABLE BUILDING OR REFURBISHMENT OR REPAIR NEEDS LIMITATIONS SET BY LEGISLATION LIMITATIONS BY LEGISLATION AND AND NATIONAL BUILDING CODE STATUTES RELATING TO BUILDING ALTERNATIVE COURSES OF ACTION OPERATION ALTERNATIVES 2. PLANNING OF BASIC SOLUTION DEFINING A BASIC SOLUTION PRELIMINARY DESIGN OF BUILDING PRELIMINARY DESIGN BASIC SOLUTION BASIC ALTERNATIVE 3. CHOICE OF SYSTEM ALTERNATIVES ON THE SYSTEM LEVEL FINDING OUT TECHNICAL SYSTEM ALTERNATIVES 1 n n Airconditioning Air conditioning : Airconditioning Air conditioning : Heat generation Heat generation: Heat generation Heat generation: eg eg. district heating . e.g. district heating e.g. district heating eg electric heating . 4. CHOOSINGPROFITABILITY OF ENERGY SAVING MEASURES STUDYING THE STRUCTURES AND HVAC EQUIPMENT 1 1 n n 1 1 n n Measure: Measure: Measure: Measure:: Investment: Investment : Investment : Investment e.g..wall eg wall e.g.. heat eg heat e.g..wall eg eg. wall e.g.. heat eg. heat eg insulation insulation recovery insulation insulation recovery recovery recovery Total solution 1 1 Integral solution alternative Total solution n n Integral solution alternative COMPARING TOTAL SOLUTIONS 5. COMPARISON OF SYSTEM TOTALITIES AND DECISION AFFORDABILITY ESTIMATES ON THE BASIS OF COMPARING THE INTEGRAL SOLUTION ALTERNATIVES LIFE-CYCLE COSTS AND VALUE FACTORS DECISION DECISIONFigure 1. Phases of systematic decision-making (Heljo & Aalto 1984, p. 12).
  4. 4. 4This methodology takes the limited financial resources as a driving constraint and assists theirallocation as effectively as possible. The methodology also aids to ensure that all possibleenergy saving measures that are economically profitable will be assessed and also probablyexecuted within refurbishments. This is important, because practice has shown that all theprofitable measures will not be executed on the basis of feeling-based decision-making. Thepresented methodology has been shown in several forms in different studies (Heljo & Aalto1984; Abel 2010; Kurvinen 2010; Vihola 2010) and is being further developed in ongoingprojects (Kurvinen & Heljo 2011; Abel 2010).Case ProjectHousing Foundation of Tampere (VTS) is a non-profit social housing company that ownsmany housing blocks in Tampere district in Finland. The foundation actively develops itsbusiness operations and it has taken part in many research projects. In 2004 VTS executed anenergy saving pilot refurbishment project, which was related to SUREURO research project(Heljo & Peuhkurinen 2004). At the moment, results and methodologies of SUREUROproject are applied and further developed in EVAKO research and development project,which pilot case is an area of 13 housing blocks owned by VTS Homes (Kurvinen & Heljo2011).Two three-storey housing blocks owned by Housing Foundation of Tampere (VTS) wererefurbished during the SUREURO project. The refurbished buildings were built in 1971 andthe project objective was to decrease energy consumption by 40 %.The following alternative refurbishment and complementary building solutions were studiedin the projects: Solution 1: refurbishment of present houses (no complementary building). Solution 2: refurbishment of present houses and building additional storeys on them. Solution 3: refurbishment of present houses, building additional storeys on them and building a five-storey extension.The 2nd of the above mentioned alternative solutions was executed.
  5. 5. 5To evaluate how the set energy saving objective could be achieved, alternative calculationswere prepared. The estimated effects of different energy saving measures are presented infigure 2. It is important to notice that energy saving calculations have been carried out in oldbuildings without taking space changes and extensions into account. 1191,0 MWh Saving 24,8 % Saving 42,3 % Saving 47,6 % Structural elements 616,0 MWh 896,1 MWh Windows 276,0 U = 2,7 Doors 67,0 U = 2,7 Structural elements 321,3 MWh Walls 119,0 U = 0,41 Windows 145,5 U = 1,4 Doors 30,5 U = 1,4 687,1 MWh Ground f loor 91,0 U = 0,50 Walls 73,6 U = 0,25 Structural elements 624,4 MWh Roof 63,0 U = 0,35 Ground f loor 36,6 U = 0,25 321,3 MWh Roof 35,1 U = 0,16 Windows 145,5 U = 1,4 Structural elements Doors 30,5 U = 1,4 321,3 MWh Windows 145,5 U = 1,4 Walls 73,6 U = 0,25 Doors 30,5 U = 1,4 Ground f loor 36,6 U = 0,25 Walls 73,6 U = 0,25 Mechanical Mechanical Roof 35,1 U = 0,16 Exhaust Exhaust Ground f loor 36,6 U = 0,25 Ventilation Ventilation Roof 35,1 U = 0,16 417,0 MWh 417,0 MWh MVHR (efficiency 50 %) MVHR 208,0 MWh (efficiency 50 %) 208,0 MWh Household water Household water Household water 158 MWh 158 MWh 158 MWh Household water 95 MWh 197 l/p/d 197 l/p/d 197 l/p/d 118 l/p/d A) Before refurbishment B) Basic solution of C) B + MVHR 50 % D) B + C + water saving refurbishment 197 l/p/d → 118 l/p/dFigure 2. The estimated effects of different energy saving measures in the pilot case. Note!Electricity consumption increases 30–40 MWh/year (it is not shown in the figure, but it istaken into account in operation costs). (Heljo & Peuhkurinen 2004, part B p. 10.)When exploiting the earlier presented methodology, the starting point for selection of energysaving measures is that basic solutions are in the first place based on other factors than energyeconomics. The basic solution of the refurbishment is usually defined on the basis of thestructural and physical minimum requirements of the building. Energy-efficiency of the basicsolution can be improved by executing different energy saving measures. To be able tochoose the most profitable measures, it is important to study their economic effects. In thispilot case, profitability of different measures is studied on the basis of the calculated internalrates of return. Internal rates of return are presented in figure 3. District heating is a naturalheat generation system for this pilot case, and thus effects of other heat generation systemswere not studied.To define the real energy economical optimum for execution of energy saving measures, theimprovements of energy-efficiency were studied stepwise. By using this methodology, limitedfinancial resources can be allocated as effectively as possible. For example, in the pilot caseadding the insulation thickness of the upper floor from 150 mm to 200 mm proved to beprofitable, but increasing thickness up to 250 mm turned out to be unprofitable.
  6. 6. 6 Selection of structural- and HVAC-technical Pay Internal Choice energy saving measures in back rate and structure- and equipment phase time (real) order (phase 4 in choice process) Price of heating energy 40 EUR / MWh Price of electricity 70 EUR / MWh y % Measure Measure Description of energy number number saving measure of alteration Wall 1 B Wall: Extra insulation of walls 80 mm (U=0,25) Wall 2 Wall:Extra insulation 100 mm (U=0,21) 2 Wall 1-2 Wall: Change of extra insulation 80-100 9 10,6 % Wall 3 Wall: Extra insulation 150 mm (U=0,17) Wall 2-3 Wall: Change of extra insulation 100-150 89 -3,4 % Win 1 B: New window U=1,8 Win 2 New window U=1,4 Win 1-2 Change of window U=1,8 - 1,4 7 13,7 % Win 3 New window U=1,0 1 Win 2-3 Change of window U=1,4 - 1,0 6 16,8 % Ufl 1 B UflY: Extra insulation of upper floor 150 mm (U=0,168) Ufl 2 Ufl: Extra insulation 200 mm (U=0,140) 4 Y 1-2 Ufl: Change of extra insulation 150 - 200 13 7,3 % Ufl 3 Ufl: Extra insulation 250 mm (U=0,120) Y 2-3 Ufl: Change of extra insulation 200 - 250 38 0,3 % Vent 1 B: Renovation of old output-ventilation system Vent 2 Concentrated input/output ventilation 5 Vent 1-2 Concentrated ventilation instead of renovation 14 6,1 % Vent 3 Deconcentrated input/output ventilation Vent 1-3 Deconcentrated ventilation instead of renovation 20 3,0 % Water Measuring of water consumption (50% saving) 8 9,1 % 3Figure 3. Profitability of studied energy saving measures. (Abbreviation B=basic solution).Number 1 always means basic solution. Numbers 2 and 3 are energy saving measures.Markings 1–2, 2–3 and 1–3 indicate changes between measures. (Heljo & Peuhkurinen 2004,part B p. 27.)According to the energy economical studies, objective of 40 % decrease in energyconsumption can be achieved, so that the result is economically profitable. If examinedenergy saving measures are arranged in profitability order, and all the profitable measureswere executed, estimated energy savings in total would be 44 %, which means the setobjective would be achieved.Measured energy consumptions before and after pilot refurbishment are presented in figure 4.The measured numbers show that the realized energy saving was not as notable as could beexpected on the basis of estimated values. The realized saving in heating energy consumptionwas only 27 %. In addition to that real estate electricity consumption increased afterrefurbishment by 45 %. This means only about 22 % decrease in total energy consumption.Hence, the objective of 40 % decrease in total energy consumption was not achieved inpractice.
  7. 7. 7 Heating energy consumption before and after refurbishment 2001–2008 300 274 276 272 250 196 204 201 200 [kWh/sqm, a] 150 100 50 0 REFURBISHMENT 2001 2002 2003 2006 2007 2008Figure 4. Measured heating energy consumption before and after refurbishment. Measuredenergy consumptions are normal year corrected. Square metres in figure are floor areasquare metres. (Heljo et al. 2012.)The fact that the estimated energy savings did not completely come true was, of course, adisappointment. In this pilot case, there are many reasons, which decreased the total energysavings. One of the most important reasons is increased level of ventilation. During therefurbishment project old mechanical exhaust ventilation system was replaced withmechanical ventilation system with heat recovery. This refurbishment measure brings a betterindoor climate, but at the same time, it causes increase in the level of ventilation. It is alsopossible that before the refurbishment the level of ventilation was significantly lower than theestimated value, which would explain a big part of the difference between the reality andestimated energy savings.Other faced problem is resident complaints, which VTS has received concerning moisturebetween window glasses. On the outermost surface of the window, moisture and frost wouldbe acceptable. However, when moisture is observed between the glasses, there is somethingwrong. HVAC specialists have doubt that the problem occurs in the pilot case because of theinsufficient low pressure in the building. It has also been doubt that structures would have gotwet during the construction process, which may also cause moisture problems.The described case project is a good example of a pilot project that did not fulfil all theexpectations. Because of the noticeable additional investment costs and caused problems, as awhole, this construction project has been considered unprofitable. Even if decisions weremade according to the earlier presented methodology, still a great amount of uncertaintiesremain involved in the refurbishment projects. On the other hand, it is good to remember thatif decision-making is feeling-based the amount of uncertainties is even bigger. In other words,the methodology does not solve all the problems, but it is still a valuable tool for decision-making.The presented methodology is being further developed in an ongoing EVAKO research anddevelopment project. The objective is to develop economic decision-making criteria for
  8. 8. 8housing companies. The criteria is developed in the first phase of pilot case, and will be putinto practice in the second phase. In figure 5 it is shown how the effects of energy savingmeasures can be described in graphic detail. By using this kind of graph, it is easy to makeclear the economical effects of measures. The information of the figure is related to EVAKOproject’s pilot case. Total Profitability of Energy Saving Measures (average lifetime 32 years; energy price 0,10 €/kWh) 5 0% 20 % 8% 6% 4% 2% 4 Annual Energy Cost Savings 3 MVHR (efficiency 60 %) [€/sqm, a] 2 Exterior Walls: Supplementary insulation +100 mm 1 New Windows (U=1,2 → U=1,0) Roof: Supplementary insulation +200 mm 0 0 20 40 60 80 100 120 140 160 Additional Cost [€/sqm]Figure 5. Total profitability of energy saving measures. The graph contains lots of essentialinformation: additional costs, annual energy cost savings and internal rate of return.(Kurvinen & Heljo 2011, p. 11.)ConclusionsDuring the last years, numerous pilot projects have shown how energy consumption can beremarkably decreased. However, in many cases the full energy saving potential is notexploited in refurbishment projects. In addition to successful pilot projects, there have beenalso cases, in which the impacts have not been as positive as expected. Disappointmentstogether with noticeably higher investment costs, as compared to basic solutions, slow downthe popularity of energy saving refurbishments much more than good examples are able toaccelerate it.In such climate conditions as Finland achieving nearly zero-energy level in refurbishments isso expensive that it is hard to give economically profitable reasons for decision-making.Hence, it would be more beneficial option to concentrate on ensuring that as big part of theeconomically profitable energy saving measures as possible would be executed withinrefurbishments. (Kurvinen 2010; Vihola 2010). Because investors will always requireprofitability for their investments, it is important to use systematic methodology in energysaving measure related decision-making. In this way the effective allocation of financialresources can be ensured and energy economically profitable measures will probably beexecuted. The methodology does not solve all the problems, but it is still a valuable tool fordecision-making.
  9. 9. 9ReferencesAalto, R & Heljo, J. 1984. Energy Saving Choices in Buildings (in Finnish). Helsinki,Rakentajain Kustannus Oy. 289 p. + appx 10 p.Abel, Enno. 2010. Economic Evaluation. BELOK Total Project – Increasing Energy-Efficiency in Swedish Non-Residential Buildings (in Swedish). [PDF]. Referred: 5.10.2011.Accessible at: http://www.belok.se/docs/Kortrapporter/Lonsamhetsmodell.pdf. 17 p.Heljo, J. & Peuhkurinen, T. 2004. Impacts of Major Refurbishments and Extensions onEnergy Consumption and LCC in Blocks of Flats (in Finnish). Tampere, Tampere Universityof Technology. Department of Construction Management. Report 2004:5. 41 p. + appx 3 p.Heljo, J., Kurvinen A., Vihola J. 2012. Improving Energy-Effectiveness of Current BuildingStock (in Finnish). Tampere, Tampere University of Technology. Department of ConstructionManagement. Report draft.Kurvinen, A. 2010. The Systematics of Energy Economical Choices in RefurbishmentProjects of Residential Houses (in Finnish). Accessible at:http://webhotel2.tut.fi/ee/Materiaali/Evako/EE2_Diplomityo_Kurvinen.pdf. Master’s thesis.Tampere, Tampere University of Technology. Department of Civil Engineering. ConstructionManagement and Economics. 109 p. + appx 32 p.Kurvinen, A. & Heljo, J. 2011. Economic Decission Making in Suburban RefurbishmentProjects (in Finnish). Referred: 5.10.2011. Accessible at:http://webhotel2.tut.fi/ee/Materiaali/Evako/Ideapankki_kannattavuusmalli_2011_05_03.pdf.Department of Civil Engineering. Construction Management and Economics. 13 p.Vihola, J. 2010. The Systematics of Energy Economical Choices in New Building of Low-Energy Residential Blocks (in Finnish). Accessible at:http://webhotel2.tut.fi/ee/Materiaali/EE3_Diplomityo_Vihola.pdf. Master’s thesis. Tampere,Tampere University of Technology. Department of Civil Engineering. ConstructionManagement and Economics. 85 p. + appx 21 p.

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