Presentation 5, Session 3 “About building's flexibility and grid interaction”

1. About building's flexibility and grid
interaction
João F. Martins, Rui Amaral Lopes
UNINOVA
Caparica, Portugal
https://cts.uninova.pt
http://energy.uninova.pt

2. Introduction
Update to the Energy Performance of Buildings Directive
• Commission proposes new rules for consumer centred clean
energy transition, to cut CO2 emissions by at least 40% by
2030
• Objectives:
1. putting energy efficiency first
2. achieving global leadership in renewable energies
3. providing a fair deal for consumers

3. Energy Performance of Buildings Directive:
• Smart, by encouraging the use of ICT and modern technologies,
including building automation and charging infrastructure for
electric vehicles, to ensure buildings operate efficiently;
• Simple, by streamlining or deleting provisions that have not
delivered the expected output;
• Supportive of building renovation, by strengthening the links
between achieving higher renovation rates, funding and energy
performance certificates as well as by reinforcing provisions on
national long-term building renovation strategies, with a view to
decarbonising the building stock by mid-century.
1. Putting energy efficiency first

4. 2. Achieving global leadership in
renewable energies
(Solar and wind technology prices have declined respectively by
80% and 30-40% between 2009 and 2015)
Consumers will benefit from stronger rights to:
• produce their own electricity, and feed any excess back to the
grid;
• organise themselves into renewable energy communities to
generate, consume, store and sell renewable energy;
• stop buying heat/cold from a district heating/cooling system if
they can achieve significantly better energy performances
themselves.

5. 3. Providing a fair deal for consumers
Clean energy in buildings is important, so:
• speed up the renovation rate of existing buildings;
• direct impact on consumers and households alike
through lower energy bills;
• creating a building renovation market for SMEs;
• long-term perspective and vision towards the
decarbonisation of buildings (by 2050).

6. Motivation / Abstract
The growing share of renewable sources goes hand in hand with the
extensive electrification of demand. Flexible energy systems
(particularly buildings), which deviate from the traditional
production response by integrating decentralized storage and
demand response, are an important part of the solution. This
presentation will address the concept of energy flexibility on
buildings, particularly on Nearly Zero Energy Buildings, and discuss
possible metrics to assess this flexibility. The impact of Nearly
Zero Energy Buildings in the electrical grid will be discussed and
several use cases will be analyzed to exemplify the usage of
flexibility metrics.

8. Are NZEBs always a healthy solution?
Rui Amaral Lopes, Pedro Magalhães, João Pedro Gouveia,
Daniel Aelenei, Celson Lima, João Martins, A case study on
the impact of nearly Zero-Energy Buildings on
distribution transformer aging, Energy, Volume 157,
2018

9. Energy Flexibility
IEA EBC Annex 67 “Energy Flexible Buildings” (2014-
2018)
www.annex67.org
Energy Flexibility of a building is the ability to manage its
demand and generation according to local climate
conditions, user needs and grid requirements. Energy
Flexibility of buildings will thus allow for demand side
management/load control and thereby demand response
based on the requirements of the surrounding grids

10. Quantifying Energy Flexibility…
Energy Flexibility depends on:
• Available storage capacity (thermal and/or non-thermal)
• Storage efficiency
• Power shifting capability
Possible methodologies to estimate Energy Flexibility :
• Evaluating the impact of applying a specific control
strategy to a specific case study (indirect approach,
analyzing the resulting operational cost savings,
reduction in CO2-emission or peak power reductions)
• Direct prediction of the energy flexibility
• Characterization in terms of its response to penalty
functions

11. Quantifying Energy Flexibility…
1. Nuytten, T., Claessens, B., Paredis, K., Van Bael, J., & Six, D. (2013). Flexibility of a combined
heat and power system with thermal energy storage for district heating. Applied Energy,
104, 583–591
2. D’hulst, R., Labeeuw, W., Beusen, B., Claessens, S., Deconinck, G., & Vanthournout, K. (2015).
Demand response flexibility and flexibility potential of residential smart appliances:
Experiences from large pilot test in Belgium. Applied Energy, 155, 79–90.
3. De Coninck, R., & Helsen, L. (2016). Quantification of flexibility in buildings by cost curves
– Methodology and application. Applied Energy, 162, 653–665.

12. Quantifying Energy Flexibility…
Rune Grønborg Junker, Armin Ghasem Azar, Rui Amaral Lopes, Karen
Byskov Lindberg, Glenn Reynders, Rishi Relan, Henrik Madsen,
Characterizing the energy flexibility of buildings and districts,
Applied Energy, 225, 2018

13. Using Energy Flexibility at community-level
to improve grid interaction of nearly Zero-
Energy Buildings
Rui Amaral Lopes, João Martins, Daniel Aelenei, Celson Pantoja
Lima,
A cooperative net zero energy community to improve load
matching,
Renewable Energy, 93, 2016,
A Cooperative Net-
Zero Energy
Community (CNet-
ZEC) is composed by
several buildings fed by
the same (micro) grid
that, together with the
electrical devices directly
connected to the grid,
cooperate to achieve
certain objectives.

14. Using Energy Flexibility at community-level
to improve grid interaction of nearly Zero-
Energy Buildings
Before…
After…

16. Final remarks
• Energy Flexibility is a TOOL not an objective…
• Energy Flexibility depends on several aspects (weather
conditions, controller quality, comfort needs,
occupancy patterns…)
• Several flexibility characteristics are needed to
characterize the energy flexibility of a system
• The Energy Flexibility characterization and use can be
improved at community-level (micro-grid)

17. References
Eurostat. (2012). “Energy, transport and environment indicators,”.
A. Athienitis and W. O’Brien. (2015). Modeling, Design, and Optimization of Net-Zero Energy
Buildings. Wiley.
Lopes RA, Magalhães P, Gouveia JoãPedro, Aelenei D, Lima C, Martins João. (2018). A case study on
the impact of nearly Zero-Energy Buildings on distribution transformer aging, Energy.
IEA EBC Annex 67. (2016). “Energy Flexible Buildings”.
Nuytten, T., Claessens, B., Paredis, K., Van Bael, J., & Six, D. (2013). Flexibility of a combined heat and
power system with thermal energy storage for district heating. Applied Energy, 104, 583–591
D‟hulst, R., Labeeuw, W., Beusen, B., Claessens, S., Deconinck, G., & Vanthournout, K. (2015).
Demand response flexibility and flexibility potential of residential smart appliances: Experiences
from large pilot test in Belgium. Applied Energy, 155, 79–90.
Stinner, S., Huchtemann, K., & Müller, D. (2016). Quantifying the operational flexibility of building
energy systems with thermal energy storages. Applied Energy, 181, 140–154.
De Coninck, R., & Helsen, L. (2016). Quantification of flexibility in buildings by cost curves –
Methodology and application. Applied Energy, 162, 653–665.
Glenn Reynders, Rui Amaral Lopes, Anna Marszal-Pomianowska, Daniel Aelenei, João Martins, Dirk
Saelens. (2018). Energy flexible buildings: An evaluation of definitions and quantification
methodologies applied to thermal storage, Energy & Buildings.

18. https://timepac2019.blogspot.com/
If you would like to have more information about this
presentation, please contact:
Authors:
João F. Martins - jf.martins@fct.unl.pt
Rui Amaral Lopes - rm.lopes@campus.fct.unl.pt
Presenter:
Maria Marques - mcm@uninova.pt