__________________________________ Marjana Sijanec Zavrl Building and Civil Engineering Institute ZRMK COST C23 COST C23, WG1 meeting Porto, January 12-13, 2006 WG1 case study 1 - Slovenia LCC & Integrated Planning Approach in Design Process of Mercator Retail Trade Shop Refurbishment

slide 2 Scope of the case study In traditional practice the reburbishment scenario is based mostly on investment costs Running costs, maintenance, repair and other life cycle costs are neglected Investor should be informed (in figures) about LCC costs before decision making at the design stage 1 - The scope of the case study is to show the benefits of planning the building refurbishment based on LCC (Life Cycle Costs) assessment    Life cycle costs of building - NPV

slide 3 Scope of the case study 2 - The scope was also to motivate the building owners (once they are aware of the most economical refurbishment scenario) to do integrated planning of refurbishment Integrated planning (IP) of refurbishment means that also a whole list of building quality aspects that can not be directly evaluated in money was taken into account, like thermal comfort, reduction of CO 2 emissions The case study is about the process – how to approach to planning of refurbishment To illustrate LCC & IP in planning of refurbishment in practice the approach was used at refurbishment of Mercator retail trade shop: Aim - to propose cost effective and environmentally friendly energy restoration scenario

slide 4 Partner Institution short description of the partner institution, e.g. Poslovni sistem Mercator d. d. / Mercator j.s.c. The biggest alimentary retail trade company in Slovenia (with 41% of market share in Slovenia) Mercator owns mainly commercial buildings: alimentary shopping centres (22 in 5 years in Slovenia and abroad), office building, M-hotel + conference centre, 1000 alimentary shops (5-40 years old, m2), 20 – 30 refurbished yearly 138 franchising shops ! – (smaller buildings all over Slovenia) The company owns their commercial buildings Company vision: energy efficient buildings, quality of indoor environment, care for the environment, CO 2 emissions reduction, business cost reduction

slide 5 1. Activities Medium size shop “Mercator na Gmajni” Preliminary discussions, agreement  (Feb. - Apr. 2004) Introductory meeting with Mercator project team  Jul  (final selection of building) Data collection  from Aug  (existing situation, refurbishment plans, energy consumption)

slide 6 1. Before General data  610 m 2  Shop, storage rooms  Built in 60-ties, in Ljubljana (3300 DD) Core Mercator project team  Department for investments  Mercator Optima architects  Head clerk

slide 7 1. Before Building envelope…  Sept Concerte frame structure Walls –  Brick U wall =1,2 W/m 2 K… Windows –  Double glazing U win = 2.4 W/m 2 K  Shop-window single gl. U win = 5.0 W/m 2 K

slide 8 Inventory of HVAC devices Refrigeration technology ! Electrical lighting  Sept Before ! Not in the hands of investment dept., but a task of technology dept. And therefore not involved in the analyses

slide 9 1. Activities Monitoring of temperature and RH… …

slide Activities

slide Tools Idea – to use commercially available tool for LCC in building refurbishment IDA-tool in use for energy calculations… LC-Profit used for LCC analysis (spreadsheet by STATSBYGG, Norway)

slide 12 LCC tools

slide Energy calculations - scenarios Definition of the model Preliminary list of measures  Implementation of energy efficient (EE) glazing / windows  Wall insulation, roof insulation …  Shading – passive cooling  EE refrigeration techniques ** (decision made separately, on the performance and reliability criteria)  Ventilation with recuperation Refurbishment scenarios - selected for energy and LCC-calculation  Scenario 0 (existing situation, no investment, only maintenance and operation costs as usual)  Scenario I (12 cm TI for envelope)  Scenario II (new windows U st =1,1W/m 2 K)  Scenario III (scenario I + scenario II)  Scenario IV (new windows U st =0,9W/m 2 K)  Scenario V (scenario I + scenario IV)  Scenario VI (scenario II + some roof insul.) Additional analyses for support of IP  Scenario VII – summer shading, natural ventilation during night time (better thermal comfort without cooling devices)…

slide 14 Simulation of thermal response & energy flows (IDA ICE tool)

slide 15 Energy use for heating Scenario 0 (existing situation, no investment, only maintenance and operation costs as usual) Scenario I (12 cm TI for envelope) Scenario II (new windows Ust=1,1W/m2K) Scenario III (scenario I + scenario II) Scenario IV (new windows Ust=0,9W/m2K) Scenario V (scenario I + scenario IV) Scenario VI (scenario II + some roof insul.) 0% -18% - 22% -33% -23% -35% -25% ENERGY SAVINGS - HEATING TI envelope 12 cm, windows 0,9 W/m2K

slide 16 Energy use for heating Electricity consumption Yearly use of heat and electricity – comparison of scenarios

slide 17 Refurbishment scenario I - VI OPERATIONAL COSTS PER YEAR Scenario 0 (existing situation, no investment, only maintenance and operation costs as usual) Scenario I (12 cm TI for envelope) Scenario II (new windows Ust=1,1W/m2K) Scenario III (scenario I + scenario II) Scenario IV (new windows Ust=0,9W/m2K) Scenario V (scenario I + scenario IV) Scenario VI (scenario II + some roof insul.) TI envelope 12 cm, windows 0,9 W/m2K

slide 18 LCC analysis – LC-Profit* Norwegian program for NPV of annual costs for:  Management  Operational costs  Maintenance and repair  Investment in building  Investment in HVAC  Investment in electricity Assumptions  Discount rate  Life time of a building Division of costs:  Owner, tenant *STATSBYGG Factors Alternativ ELECTRIC AL HVAC Constructio n Maintenanc e Operation Manageme nt Calculations Assumption s Front page

slide 19 Scenario II (new windows U g = 1,1 W/m2K) Building lifetime – 30, 40, 50, 60 years

slide 20 LCC – NPV for scenarios I - VI Investment costs, management, operating, maintenance costs NPV INVESTMENT + FUTURE COSTS IN SERVICE LIFE OF BUILDING Scenario 0 (existing situation, no investment, only maintenance and operation costs as usual) Scenario I (12 cm TI for envelope) Scenario II (new windows Ust=1,1W/m2K) Scenario III (scenario I + scenario II) Scenario IV (new windows Ust=0,9W/m2K) Scenario V (scenario I + scenario IV) Scenario VI (scenario II + some roof insul.) Windows U= 1,1 W/m 2 K

slide Outcomes The lowest CO 2 emissions alternative  based on energy simulation (Scenario III, V) The cheapest alternative  based on LCC the least cost alternative (Scenario II) Alternative carried out in the refurbishment :  based on LCC&IP - new windows (display window - from single gl. in Al frame to Ug=1.1W/m2K), roof insulation (partly), new refrigeration technique, bigger shop area (coffee bar omitted), renewed electrical lightning (Scenario VI) Refurbishment scenarios - selected for energy and LCC-calculation Scenario 0 (existing situation, no investment, only maintenance and operation costs as usual) Scenario I (12 cm TI for envelope) Scenario II (new windows Ug=1,1W/m2K) Scenario III (scenario I + scenario II) Scenario IV (new windows Ug=0,9W/m2K) Scenario V (scenario I + scenario IV) Scenario VI (new windows Ug=1,1W/m2K, roof insulation partly)

slide 22 Conclusions LCC assessment pointed out scenario II (exchange of windows Ug=1,1 W/m 2 K) to be the option with lowest NPV Scenario II lowest NPV 33 kWh/m 2 year of energy savings, 22% less energy used for heating compared to existing case, estimated heating savings EUR/year reduction of CO 2 emissions kg CO 2 /year Integrated planning showed the importance of better thermal comfort, roof insulation was added and new refrigerators – scenario VI Scenario VI implemented Additional 5% of energy savings and CO 2 emissions Existing situation energy use for heating : electricity use = 1 : 3 PREDSTAVITEV Zemeljski plin je najkakovostnejše fosilno gorivo, saj ob zgorevanju nastajata predvsem vodna para in ogljikov dioksid, drugih škodljivih produktov pa skoraj ni. Preskrba z zemeljskim plinom je zanesljiva, saj ga dobivamo iz dveh različnih območij. Z ene strani k nam priteka iz Rusije in z druge strani iz Alžirije. Vrhnika je nekako na sredini pritoka z obeh strani. Stroški ogrevanja z zemeljskim plinom so nižji, saj je cena vedno konkurenčna napram drugim energentom. Nekaj osnovnih podatkov o zemeljskem plinu: Specifična teža zemeljskega plina je 0,6788 kg/m3 in je precej manjša od specifične teže zraka, ki ima 1,293 kg/m3 v enakih pogojih. To pomeni, da se v zraku hitro dviga in se v zaprtih prostorih zadržuje pod stropom. Zemeljski plin je brez barve in skoraj brez vonja. Zaradi lažjega odkrivanja morebitnega uhajanja mu dodajamo deodorant, ki z značilnim vonjem omogoča hitro zaznavanje prisotnosti zemeljskega plina. Sestava zemeljskega plina: metan 98,2 vol.% etan 0,6 vol.% drugi ogljikovodiki 0,2 vol.% dušik 0,9 vol.% Povprečna energijska vrednost zemeljskega plina je: - spodnja kurilna vrednost 9,473 kWh/Sm3 - zgornja kurilna vrednost 10,5817 kWh/Sm3 Napotke in navodila, kako ukrepati v slučaju uhajanja zemeljskega plina in okvare vašega plinskega trošila, lahko najdete v knjižici Plin pri vas doma.Plin pri vas doma 33 kWh * 610 m2 * 1.9kg/sm3 / 10 za Sm2 = 6,27 kg CO2/m2 * 610 m2 = kg CO2 prihranka na celo stavbo pri scenariu 2

slide 23 BUT - Conclusions 2 Refurbishment was finally not focused on the envelope only, but also on improvement of functionality of the shop:  Increased shopping area  Authomatic door  Significant number of new refrigeratiors  Heat needed for refrigerators does not remain in the shop but it is used for hot water preparation. Therefore actual electricity use after refurbishment in 2005 is slightly higher comparing the existing situation 2003 Refrigerators became an important source of chill in the shop area, additional heating had to be provided. Energy use for heating has therefore increased in spite of transmission heat losses reduction.

slide 24 After, 2005 Implemented measures: Wall- ventilated metal covering, no TI Roof partly insulated (storage area) windows  EE windows double glazed U glazing = 1,1 W/m 2 K Functional changes :  shopping area bigger,  more refrigerators,  recovered heat form refrigerators used for hot water)

slide 25 After, 2005

slide 26 Use of gas and electricity before 2003 and after refurbishment 2005

slide 27 Lessons learnt  Life Cycle Cost analysis is important for building owners in retail trade sector,  Energy savings & CO2 emissions reductions could be higher (scenario III, V)  IP stimulates focusing on other building quality issues  better (thermal, visual…) comfort and quality of the service attract the customers  total energy and electricity costs increased  BUT the turnover was doubled after the refurbishment !  Future view on LCC and IP in refurbishment – well accepted, but necessary to overcome the barriers like: lack of LCC tools, lack of databases, lack of staff, tight schedules for refurbishment…  The core of the case study is rather the use of LCC and IP method in refurbishment process than actually implemented technologies and achieved savings!

slide 28 More information: Mercator Case study is a part of SAVE project LCC-REFURB – “Integrated Planning for Building Refurbishment” , co-financed by EC and Slovenian ministry MOP

slide 29 Hvala za pozornost! E-pošta: