Energy & Buildings 199 (2019) 368–380 Contents lists available at ScienceDirect Energy & Buildings journal homepage: www.elsevier.com/locate/enbuild Estimating country-specific space heating threshold temperatures from national gas and electricity consumption data S. Kozarcanin a,b,∗ , G.B. Andresen a , I. Staffell b a Department of Engineering, Aarhus University, Inge Lehmanns Gade 10, Aarhus 8000, Denmark b Centre for Environmental Policy, Imperial College London, 16 Princes Gardens, London SW7 1NE, UK a r t i c l e i n f o Article history: Received 28 January 2019 Revised 1 July 2019 Accepted 4 July 2019 Available online 4 July 2019 Keywords: Space heating threshold temperatures Buildings Summer seasons Gas consumption data Electricity consumption data Heating degree-days a b s t r a c t Space heating in buildings is becoming a key element of sector-coupled energy system research. Data availability limits efforts to model the buildings sector, because heat consumption is not directly metered in most countries. Space heating is often related to weather through the proxy of heating degree-days using a specific heating threshold temperature, but methods vary between studies. This study estimates country-specific heating threshold temperatures using widely and publicly available consumption and weather data. This allows for national climate and culture-specific human behaviour to be captured in en- ergy systems modelling. National electricity and gas consumption data are related to degree-days through linear models, and Akaike’s Information Criteria is used to define the summer season in each country, when space heating is not required. We find that the heating threshold temperatures computed using daily, weekly and monthly aggregated consumption data are statistically indifferent. In general, threshold temperatures for gas heating centre around 15.0 ± 1.7 ◦ C (daily averaged temperature), while heating by electricity averages to 13.4 ± 2.4 ◦ C. We find no evidence of space heating during June, July and August, even if heating degree-days are present. © 2019 Elsevier B.V. All rights reserved. 1. Introduction Two thirds of the energy consumed in north European homes is for space heating, compared to just around a third in the US and China [10,32,43]. In 2015, the European heating sector accounted for more than 50% of the final energy demand of 6110 TWh/year [22]. Together, the production of electricity and heat accounted for approximately 30% of total CO 2 emissions, with heat production accounting for more than half of this share [33]. Decarbonizing the energy sector and space heating in particular, is therefore cen- tral in limiting global warming. Former studies such as Kozarcanin et al. [37] or Schaeffer et al. [49] have shown that the combined impact of climate change on weather-dependent electricity gener- ation and demand is negligible. Kozarcanin et al. [37] show further that most key properties of large-scale renewable-based electric- ity system are robust against climate change. The electricity sec- tor is therefore already being decarbonized, most efficiently by in- creasing the share of renewables. However, heat does not have the same rate of technology innovation, clean options are not reducing ∗ Corresponding author at: Department of Engineering, Aarhus University, Inge Lehmanns Gade 10, 8000 Aarhus, Denmark. E-mail addresses: sko@eng.au.dk (S. Kozarcanin), gba@eng.au.dk (G.B. Andresen), i.staffell@imperial.ac.uk (I. Staffell). rapidly in cost [50,53], and so progress is very slow [11]. Natural gas, fuel oil and coal-fired boilers are the main source of heat pro- duction for the majority of European countries [23], and relatively few countries (primarily the Nordic countries) have a significant share of lower-carbon options. The decentralised nature of heating means that data on con- sumption is not readily available. Unlike electricity, heat does not need to be monitored at high time-resolution to maintain system stability, and the prohibitive cost of heat meters means they are not becoming widespread, as are electric smart meters. This lack of data is a key gap for energy systems modellers, as the diffi- culty of decarbonizing heat, and possible synergies between flexi- ble heating load and intermittent renewable generation rise up the research agenda [30]. This research seeks to support future studies on energy system research and climate change mitigation by proposing a new frame- work for improving the accuracy and ease with which country- wise energy consumption for space heating can be estimated based on underlying weather data. The focus lays on space heat demand (as opposed to water heating and cooking), as space heating is the majority of final energy demand, and is the one, which depends on external conditions such as weather. The theory of heating degree- days is frequently used in the literature as a best proxy for esti- mating the space heating requirements as, e.g., done by Berger and https://doi.org/10.1016/j.enbuild.2019.07.013 0378-7788/© 2019 Elsevier B.V. All rights reserved.