Case study report for Forskningen, Stockholm, Sweden: Three plus energy buildings (by design) with GSHPs, variable-length boreholes, ventilation recovery and pre-heating, wastewater recovery & PV panels
2021 (Engelska)Rapport (Övrigt vetenskapligt)
Abstract [en]
The report presents energy system performances for the property Forskningen consisting of three modern buildings designed as plus energy houses with 667 PV panels and a heated area of about10,590 m2. The property is located in central Stockholm, Sweden. Special features of the buildings and their shared energy system are:
• 11 boreholes of variables lengths (225-350 m) organized in a “flower” configuration with Upipes
• 1 research borehole (100 m) with coaxial borehole heat exchanger
• heating through energy-recovery ventilation system
• wastewater heat recovery
• Domestic Hot Water (DHW) needs predominant (8 m3 DHW storage)
• desuperheaters used for DHW production
• vapor injection heat pump cycles
• no auxiliary heating system
• apartments well-equipped with sensors (more than 2000 sensors and alarms)
• distributed temperature measurement in boreholes with fiber optics
The monitoring period only extends from 2019-05-26 to 2020-02-03 (except for electricity consumption and production for which data is available for about two years). The energy needs for a full year could nevertheless be estimated and are: 257 MWh/yr (24.3 kWh/(m2 yr)) for heating and 442 MWh/yr (41.7kWh/(m2 yr)) for DHW. The ventilation heat recovery (no included in the heating needs) are estimated to cover a large part of the heating supplied to the buildings (about 70%). Performance factors (PFs) 1, 4, 4+, 5 and 5+ are presented (based on the definitions developed in the Annex 52, see part “Performance metrics” for more details). In addition, two extra PFs are introduced,5* and 5*’ which account for the whole fan energy and the ventilation heat recovery, respectively. For the whole monitored period, PF1 is about 3.6 while PF4 and PF5 are about 3.0 and 2.5, respectively. The electricity values available for about two years allows checking the claim of the buildings being plus energy. Unfortunately, there is a deficit of consumption varying between 50 to 90 MWh/yr. Besides performances, uncertainties are briefly discussed and the author performs verifications on the available data. It appears that data cannot be blindly trusted and requires a minimum level of interpretation. A short investigation about the relevance of cooling the ventilation incoming air to recharge the boreholes is conducted and it counter-intuitively appears that it can make sense to do so. Finally, a list of 10 improvement measures is provided, though some of them perhaps pertain to design considerations and improvements.
Ort, förlag, år, upplaga, sidor
2021. , s. 46
Serie
IEA HPT Annex 52 - Long-term performance monitoring of GSHP systems for commercial, institutional and multifamily buildings
Nyckelord [en]
Ground source heat pump, monitoring, performance, plus-energy buildings, SPF, ventilation heat recovery, pre-heating, waste-water heat recovery, PV, boreholes
Nationell ämneskategori
Energiteknik Husbyggnad Energisystem
Forskningsämne
Energiteknik
Identifikatorer
URN: urn:nbn:se:kth:diva-307181DOI: 10.23697/dfs2-v474OAI: oai:DiVA.org:kth-307181DiVA, id: diva2:1627959
Projekt
IEA HPT Annex 52
Forskningsfinansiär
Energimyndigheten, 45979-1
Anmärkning
This report is part of the work within IEA HPT Annex 52 - IEA HPT Annex 52 - Long-term performancemonitoring of GSHP systems for commercial, institutional and multi-family buildings, with project periodJanuary 1st 2018 to December 31 2021. Annex 52 Operating Agent is Sweden.Annex 52 aims to survey and create a library of quality long-term measurements of GSHP systemperformance for commercial, institutional and multi-family buildings. While previous work will besurveyed, the emphasis of the annex is on recent and current measurements. The annex also aims torefine and extend current methodology to better characterize GSHP system performance servingcommercial, institutional and multi-family buildings with the full range of features shown on the market,and to provide a set of benchmarks for comparisons of such GSHP systems around the world.The results from the annex will help building owners, designers and technicians evaluate, compare andoptimize GSHP systems. It will also provide useful guidance to manufacturers of instrumentation andGSHP system components, and developers of tools for monitoring, controlling and fault detection/diagnosis. This will lead to energy and cost savings.The work reported in this document was mainly performed by Willem Mazzotti Pallard at the RoyalInstitute of Technology (KTH) with support from his colleagues also involved in Annex 52: AlbertoLazzarotto, José Acuña and Mohammad Abuasbeh. Other KTH colleagues, Jonas Anund Vogel, in hisquality of director of the KTH Live-in Lab, Safira Figueiredo Monteiro and Davide Rolando, should bethanked for their indirect contributions to the project. In particular, Davide helped building the historicaldatabase, which has been useful for this project.In the text, you will find information and performance analysis of the original testbed of the KTH Live-inLab: three building on KTH main campus with about 305 student accommodations, 12 boreholes, 3ground source heat pumps, DHW dominated needs, heat recovery through ventilation and wastewater,667 PV panels and more. The results specific to these buildings are interesting per say, but there arealso more general things discussed, such as data quality and verification – can we blindly trust data?probably not – uncertainty analysis and some design considerations. In particular,The work that has led to this report has been funded by the Swedish Energy Agency(Energmyndigheten) through the project 45979-1.
2022-01-142022-01-142024-03-15Bibliografiskt granskad