Potential of control strategies to enhance energy flexibility in residential buildings in Catalonia

Transcription

1 Potential of control strategies to enhance energy flexibility in residential buildings in Catalonia Open workshop Energy Flexibility in Buildings: a key asset in the future energy system Palau Robert, Barcelona, 26 th March 2018 THIBAULT PÉAN PhD candidate at IREC & UPC tpean@irec.cat This project has received funding from the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement No

2 Introduction Role of heat pumps Control strategies RBC example Further research 2 AGENDA Challenges in electricity grid The role of heat pumps Control strategies for flexibility Example and tuning of a RBC strategy applied to Catalan building typology Current and further research Victor Enrich

3 Installed capacity (GW) Introduction Role of heat pumps Control strategies RBC example Further research 3 INTRODUCTION Challenges faced mostly by the power grid: increased penetration of variable renewables in the grid (solar & wind) Annual additions Electricity becomes greener but more variable and unpredictable Buildings possess a built-in thermal storage which presents potential for load shifting Wind power [GW] Solar power [GW]

4 Introduction Role of heat pumps Control strategies RBC example Further research 4 WHY HEAT PUMPS? BUILDING Potential thermal storage? ELECTRICITY GRID Greener but more variable

5 Introduction Role of heat pumps Control strategies RBC example Further research 5 WHY HEAT PUMPS? Heat pumps are a logical solution to play with the flexibility potential, and store thermal energy within the building mass BUILDING Potential thermal storage HEAT PUMP Use of electricity Production of heat/cold High COP ELECTRICITY GRID Greener but more variable

6 Introduction R ole of he a t pumps Control strategies RBC example Further research 6 Role of heat pumps in the energy transition MARKET AND POLICIES Heat pumps are the future! Source: IEA ETP 2017

7 Introduction R ole of he a t pumps Control strategies RBC example Further research 7 MARKET AND POLICIES Role of heat pumps in the energy transition: scenario of -85% CO 2 emissions Air-source heat pumps Ground-source heat pumps Gas heat pumps Source: H. Henning, The Role Of Heat Pumps In The Transformation Of National Energy Systems Example, 12 th Heat Pump Conference Rotterdam, May 2017.

8 Introduction R ole of he a t pumps Control strategies RBC example Further research 8 TRENDS IN THE MARKET Electrification of dwellings (from 31% in 2014 to 55% in 2050) New functionalities being implemented: compatibility with PV, SG-ready or HP tariff in Germany Good potential for air/air HPs in passive houses with an existing ventilation system Air source heat pumps are the most dynamic sector, ground source HPs are losing market share Solar Decathlon 2012 in Madrid: solar powered houses Large demand response potential (298 GW) but HPs are not smart-controlled yet because of lack of business cases In Spain market dominated with air/air HPs, around 600k units installed, market share of 15% in 2013 (

9 Introduction R ole of he a t pumps Control strategies RBC example Further research 9 TRENDS IN THE HEAT PUMP MARKET Source: Cooper Zhao. China air source heat pump market development, 12 th Heat Pump Conference Rotterdam, May 2017.

10 Introduction R ole of he a t pumps Control strategies RBC example Further research 10 HEAT PUMP MANUFACTURERS ARE PREPARING Smart-Grid Ready label (Germany) Source: D. Fischer, T. Wolf, and M.-A. Triebel, Flexibility of heat pump pools: The use of SG- Ready from an aggregator s perspective, 12th IEA Heat Pump Conf., pp. 1 12, 2017.

11 Introduction Role of heat pumps Control stra te gie s RBC example Further research 11 CONTROL STRATEGIES FOR FLEXIBILITY WITH HEAT PUMPS Control strategies acting at the supervisory level Algorithm which decisions are based on information retrieved from sensors/external input signals Control actions (for ex, SGready inputs) Sends signal to the heat pump (local controller)

12 Introduction Role of heat pumps Control stra te gie s RBC example Further research 12 CONTROL STRATEGIES FOR FLEXIBILITY WITH HEAT PUMPS??? Control strategies acting at the supervisory level Algorithm which decisions are based on information retrieved from sensors/external input signals Control actions (for ex, SGready inputs) Sends signal to the heat pump (local controller)

13 Introduction Role of heat pumps Control stra te gie s RBC example Further research 13 CONTROL STRATEGIES FOR FLEXIBILITY WITH HEAT PUMPS Role of the supervisory control, key challenges: When is it more profitable to use electricity, and when not? Based on which criteria? Which external signals can we use to help making this decision? How complex and accurate should this decision process be?

14 Introduction Role of heat pumps Control stra te gie s RBC example Further research 14 RBC vs. MPC Rule-Based Control (RBC) Simple algorithm (if condition, then action) Easy to implement No need for a model or optimization framework Overall good performance with regards to the declared objective Importance of a good tuning Inability to anticipate/predict Model Predictive Control(MPC) Optimization problem Requires a model Requires computational power Requires access to external data or prediction of disturbances Outperforms RBC Can deal with multi-objectives

15 Introduction Role of heat pumps Control stra te gie s RBC example Further research 15 MODEL PREDICTIVE CONTROL

16 Introduction Role of heat pumps Control stra te gie s RBC example Further research 16 RBC vs. MPC Rule-Based Control (RBC) Simple algorithm (if condition, then action) Easy to implement No need for a model or optimization framework Overall good performance with regards to the declared objective Importance of a good tuning Inability to anticipate/predict Model Predictive Control(MPC) Optimization problem Requires a model Requires computational power Requires access to external data or prediction of disturbances Outperforms RBC Can deal with multi-objectives

17 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 17 AN APPLIED EXAMPLE OF RBC WITH HEAT PUMP Residential flat in Terrassa, Catalonia Refurbished Air/water heat pump + radiators Flexibility control strategy Model and simulation in TRNSYS

18 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 18 FLEXIBILITY CONTROL STRATEGY (RBC) Fixing thresholds on the electricity price Consequent modulation of the heating set-points For domestic hot water (DHW) or space heating (SH)

19 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 19 FLEXIBILITY CONTROL STRATEGY (RBC) Fixing thresholds on the electricity price Consequent modulation of the heating set-points For domestic hot water (DHW) or space heating (SH) Low price Upwards modulation High price Downwards modulation

20 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 20 FLEXIBILITY INDICATOR Analysis during one week in January 2017 Flexibility factor varying between -1 (no flexibility) and 1 (high flexibility) Significant improvement when the specified strategy is implemented No flex. Flex. on SH Flex. on SH&DHW

21 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 21 TUNING OF THE CONTROL STRATEGY : : : : : : : : : : :00 Low threshold High threshold 10th percentile 90th percentile 20th percentile 80th percentile 30th percentile 70th percentile 40th percentile 60th percentile value Choice of the thresholds is crucial!

22 Introduction Role of heat pumps Control strategies R BC e x a mple Further research 22 CHARACTERIZATION OF THE FLEXIBILITY POTENTIAL 8 kwh 4 kwh 14 kwh Example of upwards modulation of different durations, starting at 13: 5 hours (+1 C) enable to store 14 kwh 2 hours (+1 C) enable to store 8 kwh 1 hour (+1 C) enable to store 4 kwh Useful info for a potential aggregator!

23 Introduction Role of heat pumps Control strategies RBC example Furthe r re se a rch 23 CURRENT & FURTHER RESEARCH Different input signals than price: residual load, CO 2 emissions (marginal or not), RES share etc Flexibility for cooling operation, relevant for Spain and the Mediterranean climate area Model predictive control with different objectives Tests with a real heat pump in semi-virtual environment

24 Introduction Role of heat pumps Control strategies RBC example Furthe r re se a rch 24 CURRENT & FURTHER RESEARCH System load Residual load = System load Production of RES CO 2 emissions factor of the energy mix Marginal CO 2 emissions factor (emissions for producing or saving 1 kwh more of energy Electricity price (dynamic prices sent to smart meters) Share of renewables in the energy mix

25 Introduction Role of heat pumps Control strategies RBC example Furthe r re se a rch 25 CURRENT & FURTHER RESEARCH Different input signals than price: residual load, CO 2 emissions (marginal or not), RES share etc Flexibility for cooling operation, relevant for Spain and the Mediterranean climate area Model predictive control with different objectives Tests with a real heat pump in semi-virtual environment

26 Thanks for your attention!

27 Introduction Role of heat pumps Control strategies RBC example Furthe r re se a rch 27 References T. Péan, J. Ortiz and J. Salom (2017). Impact of Demand-Side Management on Thermal Comfort and Energy Costs in a Residential nzeb. Buildings, vol. 7, no. 2, p. 37. DOI: /buildings T. Péan, J. Salom and J. Ortiz (2017). Potential and optimization of a price-based control strategy for improving energy flexibility in Mediterranean buildings. Energy Procedia, vol. 122, pp , Sep DOI: /j.egypro (poster presented at CISBAT 2017 International Conference on Future Buildings & Districts Energy Efficiency from Nano to Urban Scale, Sept. 6-8 th 2017, Lausanne, Switzerland) T. Péan, J. Salom and R. Costa-Castelló (2018). Review of control strategies for improving the energy flexibility provided by heat pump systems in buildings. J. Process Control, Special Issue on Efficient Energy Management, 2018 (accepted). T. Péan, B. Torres, J. Ortiz and J. Salom (2018). Representation of daily profiles of building energy flexibility. In proceedings of esim 2018 IBPSA Canada biennial Conference on Building simulation to support building sustainability, May 9-10 th 2018, Montréal, Canada (accepted).