Feasibility analyses relative to energy retrofitting of acute hospitals and community clinics

Transcription

1 SOSTENIBILITA AMBIENTALE E PRODUZIONE EDILIZIA La ricerca scientifica sulla Produzione Edilizia nell era delle nuove sfide ambientali nel Settore delle Costruzioni Feasibility analyses relative to energy retrofitting of acute hospitals and community clinics M. Lemma, P. Prinicpi, R. Fioretti, A. Carbonari Convegno ISTeA 2015 Politecnico di Milano settembre 2015

2 RENOVATING THE EXISTING PUBLIC STOCK Background: The existing building stock is responsible for a huge amount of energy consumption in Europe EU Directive 2012/27/UE target: 3% of the public stock retrofitted every year Main Players: Public administrations Novel strategies: Advantageous financial schemes (e.g. Energy Performance Contracting) Retrofit technologies easy to install in strategic buildings Customisation of technologies and knowledge transfer to the staff of the public administration

3 ENERGY PERFORMANCE CONTRACTING (EPC) EPC is a financing technique that uses energy/utility cost savings from reduced consumption to repay the cost of installing energy conservation measures. Related energy/utility projects are undertaken by Energy Services Companies (ESCos), that implement renovation actions as soon as the contracts have been signed. This approach has already been subject to testing in the USA and North Europe. Subsidies are sometimes included for armonization of the EPC s loan. Marte is funded by IEE (Intelligent Energy Europe) programme - MLEI actions: Mobilising Local Energy Investment.

4 THE PROJECT «MARTE» MARTE is the acronym for: Marche Region Technical assistance for healthcare buildings Energy retrofit List of partners: Regione Marche Public authority Coordinator, energy policy, fundraising Azienda Sanitaria Unica Regionale (ASUR) Agenzia per l Energia e lo sviluppo sostenibile di Modena (AESS) Università Politecnica delle Marche (UNIVPM) Società Italiana dell Architettura e dell Ingegneria per la Sanità (SIAIS) Public authority Energy agency University No profit association Technical, public procurement Technical, public procurement, financial expert Technical expert Policy, training and communication

5 to assess the feasibility of energy renovation of healthcare buildings with the EPC funding scheme to evaluate energy saving potentials for two groups of healthcare buildings: -acute hospitals (no. 3 cases) OBJECTIVES OF MARTE PROJECT -community clinics (no. 2 cases) to make the methodology standardized and replicable for other pubic sectors, such as council housing and local administrations (e.g. municipalities) to enhance decision making capabilities about EPC of managers and technical staff of public institutions

6 THE CASE STUDIES No. 3 ACUTE HOSPITALs No. 2 COMMUNITY CLINCs Id (City) San Benedetto del Tronto Climatic Zone [Italian legislation] Degree days Number of floors S u [m 2 ] V [m 3 ] Ratio S/V Time of construction D s-1980s Urbino E s-1990s Pergola E s Sant Elpidio a mare D (3444) Petritoli D (3229) (15239) (16292) 0.41 (0.32) 0.56 (0.48) 1970s-1980s 1970s-1980s

7 THE METHODOLOGY FOR ENERGY AUDIT 1. Data gathering about the current energy consumption (ref. EN par. 5.3 Collecting data ), extended 3 years backwards. 2. Calibration of energy simulation models of the five hospitals implemented in the software Mc4Suite 2013 (validated by CTI), i.e. the benchmark. 3. [this step applies just to community clinics] Development of the estimated benchmark, i.e. those models that fix the reference situation at the future moment in time when the building will start to be managed by an ESCo. In fact the 2 clinics will be extended with an additional division (nursing home and some more clinics). 4. Estimation of the benefits deriving from several combinations of retrofit strategies (ref. EN ). 5. Economic analyses: estimate summary and payback period for each scenario.

8 No. 3 ACUTE HOSPITALs No. 2 COMMUNITY CLINCs ENERGY RENOVATION STRATEGIES ASUR owns tens of buildings this size. They are responsible for a huge fraction of the overall energy consumption and cost due to building conditioning in ASUR (around 20 mil per year). Even if a limited number of these buildings is retrofitted, it will determine considerable costs savings. So they were considered as priority 1 buildings to be retrofitted. ASUR owns hundreds of buildings this size. Even though every single building does not generate high energy consumption, all together they are responsible for a huge fraction of the overall energy consumption in ASUR. Hence, only easily replicable energy renovation actions may determine considerable savings. It is feasible just in case customized and easy to install methodologies and technologies are adopted.

9 Id San Benedetto del Tronto BENCHMARK ANALYSES Gas Methane [kwh/m 3 y] Electricity [kwh/m 3 y] EP H [kwh/m 3 y] EP H,L [kwh/m 3 y] EP w [kwh/m 3 y] Urbino Pergola Petritoli (52.2) 10.9 (9.4) 10.9 (6.3) 59.0 Sant Elpidio a mare Relevant comments: (39.2) 14.4 (13.1) 19.4 (9.8) 45.8 acute hospitals present higher energy consumption, due to the higher number of daily occupation; the use of community clinics has been changing over the years (the future arrangement will set the clinics parameters as indicated in brackets) Heating consumption of the clinics is relatively high, if compared with the average 8 hours daily occupation. gl [%]

10 POST-RETROFIT SCENARIOS Id (Location) Actions EP H San Benedetto del Tronto Urbino Pergola Petritoli Sant Elpidio a Mare retrofit of whole envelope and heating generation and control system Retrofit of whole envelope and control system. Starting CHP. retrofit of whole envelope and heating generation and control system Windows replac., roof insul., new heat generation and regulation, lighting and solar panels Windows replac., new heating system regulation, lighting and solar panels [kwh/m 3 year] energy reduction [%] initial investment [k ] cost reduction [k /year] GHG reduction [kgco 2 /y] PBP [year] (heating) 49.8% (electric) 32.4% 19.4 (heating) 33.9% (electric) 47.4%

11 COMPARISON BETWEEN THE CHOSEN PILOTS As a result of the energy audit, acute hospitals resulted to be suitable for wide energy renovation actions: improved insulation of envelopes, full replacement of windows, replacement of the heating central plant and control system, integration of solar panels. This set of actions is very expensive. The EPC scheme can be partially applied, because more than 50% of the costs must be afforded by the owner their selves or by means of subsidies. Low cost energy renovation actions were assumed for the community clinics, such as: enhancement of the existing regulation systems, partial replacement of the oldest-aged windows, partial replacement of light fixtures with Led lamps and Dali control system. As a result, payback periods are quite limited, although not fully compatible with the time period an EPC contract can be in force.

12 SELECTED LOW-COST SCENARIOS A specific combination of low-cost actions might be selected for community clinics, in order to make the actions economically feasible within the duration of the EPC contract. Hypotheses: no subsidies are available, 5.5% interest rates. Peculiarities: the buildings are in operation 8 hours per day. Arrangement of divisions may often change over the years. Sant Elpidio a Mare (2nd floor) Jan. to June 2013: clinics June to Dec. 2013: unoccupied Expected benchmark: nursing home Petritoli (1st floor) Present situation to expected benchmark

13 Diagnosis: SIMULATED LOW-COST SCENARIOS No control system or old-aged regulation system Obsolete generation systems and high distribution losses Poor lighting system Low level of insulation Renovation actions: roof enhanced insulation, replacement of old heat generators, new control system of the heating plant, partial replacement of the lighting fixtures, enhanced insulation of the distribution sub-system in the heating system.

14 RESULTS Results from the simulation of the low cost scenarios as compared with the expected benchmarks: Petritoli (scenario 1) Petritoli (scenario 2) Id actions energy Sant Elpidio a Mare Roof enhanced insulation, new heat generation and regulation Roof enhanced insulation, new heat generation and regulation, partial replacement with a Dali controlled led lighting system New heating system regulation, enhanced insulation of the distribution system reduction [%] (heating) 43.2% (electric) 7.0% (heating) 43.2% (electric) 32.9% (heating) 10.8% (electric) 4.4% initial investment [k ] cost reduction [k /year] PB (i=5.5%) [year]

15 CONCLUSIONS Extensive wide energy renovation in public buildings cannot be supported just by EPC funding schemes; In most cases public incentives are necessary in order to make the investments affordable; Low-cost scenarios can be considered for those buildings that can be subject to minor renovation actions, provided that: accurate diagnosis is performed in energy audits; accurate simulations are performed to evaluate benefits brought in by minor renovations actions; customized technologies are identified; technical feasibility is verified prior to start retrofitting.