Space heating emission systems EN 15316 -2 1

Space heating emission systems EN 15316 -2. 1: Emission and control Bjarne W. Olesen International Centre for Indoor Environment and Energy Technical University of Denmark bwo@byg. dtu. dk Contract: EIE/07/069/SI 2. 466698 Duration: October 2007 – March 2010 Version: July 7, 2009

Outline • The EU CENSE project • Scope of the Standard • Heat emission systems • German method • French method • Example slide 2

The EU CENSE project (Oct. 2007 - March 2010) Aim of the project: To accelerate adoption and improved effectiveness of the EPBD related CEN- standards in the EU Member States These standards were successively published in the years 2007 -2008 and are being implemented or planned to be implemented in many EU Member States. However, the full implementation is not a trivial task Main project activities: A. To widely communicate role, status and content of these standards; to provide guidance on the implementation B. To collect comments and good practice examples from Member States aiming to remove obstacles C. To prepare recommendations to CEN for a “second generation” of standards on the integrated energy performance of buildings slide 3

Brief introduction A brief introduction to the CENSE project and the CEN-EPBD standards is provided in a separate presentation: slide 4

More information and downloads: www. iee-cense. eu Disclaimer: CENSE has received funding from the Community’s Intelligent Energy Europe programme under the contract EIE/07/069/SI 2. 466698. The content of this presentation reflects the authors view. The author(s) and the European Commission are not liable for any use that may be made of the information contained therein. Moreover, because this is an interim result of the project: any conclusions are only preliminary and may change in the course of the project based on further feedback from the contributors, additional collected information and/or increased insight. slide 5

Use of EN 15316 -2. 1 The calculation method is used for the following applications: • Calculation of the additional energy losses in the heat emission system; • Optimisation of the energy performance of a planned heat emission system, by applying the method to several possible options; • Assessing the effect of possible energy conservation measures on an existing heat emission system, by calculating the energy requirements with and without the energy conservation measure implemented. slide 6

Scope of EN 15316 -2. 1 • Standardise the required inputs, the outputs and the approach used in the calculation method, in order to achieve a common European calculation method. • The energy performance may be assessed either in terms of the heat emission system efficiency or in terms of the increased space temperatures due to heat emission system inefficiencies. • The methods are based on the analysis of the following characteristics of a space heating emission system, including its control: • non-uniform space temperature distribution; • emitters embedded in the building structure; • control accuracy of the indoor temperature. slide 7

Scope of EN 15316 -2. 1 The energy required by the emission system is calculated separately for thermal energy and electrical energy in order to determine the final energy, and subsequently the corresponding primary energy is calculated. The calculation factors for conversion of energy requirements to primary energy shall be decided at a national level. slide 8

Energy performance of heat emission systems Calculation concept and building-system boundaries for heating EN 15316 -1

Heat energy losses of heat emission They are calculated as: Qem, ls = Q em, str + Q em, emb + Q em, ctr [J] where: (1) Qem, str heat loss due to non-uniform temperature distribution in Joule (J); Qem, emb heat loss due to emitter position (e. g. embedded) in Joule (J); Qem, ctr heat loss due to control of indoor temperature in Joule (J). slide 10

Method using efficiencies of the emission system QH fhydr fint fradiant ηem is the additional loss of the heat emission (time period), in J is the net heating energy (time period) (EN ISO 13790), in J; is the factor for the hydraulic balancing. is the factor for intermittent operation (intermittent operation is to be understood as a time-dependent option for temperature reduction for each individual room space); is the factor for the radiation effect (only relevant for radiant heating systems); is the total efficiency level for the heat emission in the room space slide 11

Total efficiency level ηem where ηstr is the partial efficiency level for a vertical air temperature profile; ηctr is the partial efficiency level for room temperature control; ηemb is the partial efficiency level for specific losses from the external components (embedded systems). slide 12

Emission factors Default values for the different efficiencies and factors can be found in an informative annex to the standard. Some of these values are based on real data from experiments and/or computer simulations, while others are based on a consensus • Factor for intermittent operation fint : – Radiator – Floor heating = 0. 98 = 0. 97 • Factor for radiation effect: frad = 1. 0 slide 13

Factors for hydraulic balancing slide 14

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Examples • • • Radiator external wall; over-temperature 42. 5 K; P-controller (2 K) ηstr = (ηstr 1 + ηstr 2 )/2 = (0. 93 + 0. 95)/2 = 0. 94 ηctr = 0. 93 ηemb = 1 ηem = 1/(4 – (0. 94 + 0. 93 + 1)) = 0. 88 • Floor heating - wet system (water); two-step controller; floor heating with minimum insulation • ηstr = 1. 0 • ηctr = 0. 93 • ηemb = (ηemb 1 + ηemb 2 )/2= (0. 93 + 0. 95)/2 = 0. 94 • ηem = 1/(4 – (1. 0 + 0. 93 + 0. 94)) = 0. 88

Single family house slide 18

Net Energy for the house EN ISO 13790 Net Energy-House Building k. Wh/m 2 180 160 140 120 100 80 60 DHW Heating 40 20 0 Venice Brussels Stockholm slide 19

Heat losses in the heat emission system slide 20

Heat losses in the heat emission system Stockholm Qem ΔT ηstr 1 ηstr 2 ηemb P(2 K) Qh = 66, 42 k. Wh/m² 1 30 0, 95 1 P (2 K) P (1 K) 22, 5 0, 96 0, 95 1 PI 11, 4 8, 6 0, 90 15, 6 9, 6 7, 3 0, 92 12, 8 7, 9 6, 0 0, 89 17, 0 10, 5 8, 0 0, 91 14, 2 8, 8 6, 6 0, 93 11, 3 7, 0 5, 3 0, 95 18, 4 0, 97 0, 93 0, 88 0, 93 Radiators (boiler) P (1 K) 55/45/20 PI 0, 90 16, 3 10, 1 7, 6 0, 91 13, 5 8, 3 6, 3 0, 93 10, 6 6, 6 5, 0 0, 95 0, 94 0, 955 0, 97 Floor heating P-control 35/28 PI-control Floor heating P-control extra insulation PI-control ηemb 1 ηemb 2 ηemb 0, 93 0, 95 0, 94 0, 93 0, 99 0, 96 ηstr ηem 0, 93 1 0, 89 18, 4 11, 4 8, 6 1 0, 90 15, 6 9, 6 7, 3 0, 92 12, 8 7, 9 6, 0 0, 93 9, 9 6, 1 4, 6 0, 95 7, 1 4, 4 3, 3 0, 93 1 0, 95 P-control 0, 93 1 PI-control ηctr 0, 95 Floor heating No downwards loss ηem Qh = 87, 55 0, 97 42, 5 P (2 K) ηstr 0, 93 Radiators (boiler) P(1 K) 70/55/20 PI Radiators (Heat Pump) 50/35/20 ηctr Venice Qem Qh = 141, 85 Residential Brussels Qem 1 1 1 0, 95 slide 21

Method using equivalent increase in internal temperature The equivalent internal temperature, θint, inc taking into account the emitter, is calculated by: where: • θint, initial internal temperature (°C); • Δθstr spatial and vertical variation of temperature; • Δ θctr control variation. Input values for different emission systems and controls can be found in the annex. slide 22

Method using equivalent increase in internal temperature The influence of an equivalent increase in internal temperature due to losses from the heat emission system may be calculated in two different ways: 1. By multiplying the calculated building heat demand, QH, with a factor based on the ratio between the equivalent increase in internal temperature, qint, inc, and the average temperature difference for the heating season between the indoor and outdoor temperatures for the space: Qem = QH · ( θint, inc / ( int, inc - e, avg) ) [J] 2. By recalculation of the building heat energy requirements, according to EN ISO 13790, using the equivalent increased internal temperature as the set point temperature of the conditioned zone. This second approach leads to better accuracy. slide 23

More information and downloads: www. iee-cense. eu Disclaimer: CENSE has received funding from the Community’s Intelligent Energy Europe programme under the contract EIE/07/069/SI 2. 466698. The content of this presentation reflects the authors view. The author(s) and the European Commission are not liable for any use that may be made of the information contained therein. Moreover, because this is an interim result of the project: any conclusions are only preliminary and may change in the course of the project based on further feedback from the contributors, additional collected information and/or increased insight. slide 24