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Opportunities and challenges in energy demand reduction for Canadian residential sector: A review

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  • Karunathilake, Hirushie
  • Hewage, Kasun
  • Sadiq, Rehan

Abstract

Developing energy independent and sustainable communities has gained a high level of global interest in recent times. The Federal Sustainable Development Strategy for Canada (FSDS) has defined the addressing of climate change and the shrinking of the environmental footprint as priority themes in its sustainable development approach. In the pursuit of planning net-zero to net-positive community energy systems, reducing the energy demand of the residential buildings is the first priority, particularly as the residential sector accounts for 17% of the secondary energy use in Canada. Various technical, behavioural, and policy level interventions are available for reducing residential energy consumption. In this review, demand reduction interventions have been categorised as efficiency, saving and conservation measures. The benefits, limitations and challenges present in adopting those strategies are discussed for various regions in Canada. Even though there is an advanced level of knowledge available on energy demand reduction, the scattered information needs to be brought together to develop a combined and inclusive approach for residential demand management. Collected knowledge will inform decision makers engaged in the design of residential buildings and planning of sustainable communities to identify the interventions which can be implemented in a given locality. This review aims to address the above gaps through a comprehensive review on potential energy demand reduction methods, especially for Canada. The implications of the findings to Canadian residential energy sector as a whole are discussed in the final part of the review.

Suggested Citation

  • Karunathilake, Hirushie & Hewage, Kasun & Sadiq, Rehan, 2018. "Opportunities and challenges in energy demand reduction for Canadian residential sector: A review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 82(P3), pages 2005-2016.
    • Handle: RePEc:eee:rensus:v:82:y:2018:i:p3:p:2005-2016
    DOI: 10.1016/j.rser.2017.07.021
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    1. Mansilla, R. & Köppen, E. & Cocho, G. & Miramontes, P., 2007. "On the behavior of journal impact factor rank-order distribution," Journal of Informetrics, Elsevier, vol. 1(2), pages 155-160.
    2. Berardi, Umberto, 2013. "Stakeholders’ influence on the adoption of energy-saving technologies in Italian homes," Energy Policy, Elsevier, vol. 60(C), pages 520-530.
    3. Spyros Arvanitis & Marius Ley, 2013. "Factors Determining the Adoption of Energy-Saving Technologies in Swiss Firms: An Analysis Based on Micro Data," Environmental & Resource Economics, Springer;European Association of Environmental and Resource Economists, vol. 54(3), pages 389-417, March.
    4. Acosta, Ignacio & Munoz, Carmen & Campano, Miguel Angel & Navarro, Jaime, 2015. "Analysis of daylight factors and energy saving allowed by windows under overcast sky conditions," Renewable Energy, Elsevier, vol. 77(C), pages 194-207.
    5. Hinnells, Mark, 2008. "Technologies to achieve demand reduction and microgeneration in buildings," Energy Policy, Elsevier, vol. 36(12), pages 4427-4433, December.
    6. Lucas W. Davis, 2011. "Evaluating the Slow Adoption of Energy Efficient Investments: Are Renters Less Likely to Have Energy Efficient Appliances?," NBER Chapters, in: The Design and Implementation of US Climate Policy, pages 301-316, National Bureau of Economic Research, Inc.
    7. Loi, Tian Sheng Allan & Loo, Soh Leng, 2016. "The impact of Singapore’s residential electricity conservation efforts and the way forward. Insights from the bounds testing approach," Energy Policy, Elsevier, vol. 98(C), pages 735-743.
    8. Boßmann, Tobias & Eser, Eike Johannes, 2016. "Model-based assessment of demand-response measures—A comprehensive literature review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 57(C), pages 1637-1656.
    9. Wiel, Stephen & McMahon, James E., 2003. "Governments should implement energy-efficiency standards and labels--cautiously," Energy Policy, Elsevier, vol. 31(13), pages 1403-1415, October.
    10. Mills, Bradford & Schleich, Joachim, 2010. "What's driving energy efficient appliance label awareness and purchase propensity?," Energy Policy, Elsevier, vol. 38(2), pages 814-825, February.
    11. Sadineni, Suresh B. & Madala, Srikanth & Boehm, Robert F., 2011. "Passive building energy savings: A review of building envelope components," Renewable and Sustainable Energy Reviews, Elsevier, vol. 15(8), pages 3617-3631.
    12. Stephan, André & Stephan, Laurent, 2016. "Life cycle energy and cost analysis of embodied, operational and user-transport energy reduction measures for residential buildings," Applied Energy, Elsevier, vol. 161(C), pages 445-464.
    13. Chan, Hoy-Yen & Riffat, Saffa B. & Zhu, Jie, 2010. "Review of passive solar heating and cooling technologies," Renewable and Sustainable Energy Reviews, Elsevier, vol. 14(2), pages 781-789, February.
    14. Gyberg, Per & Palm, Jenny, 2009. "Influencing households' energy behaviour--how is this done and on what premises?," Energy Policy, Elsevier, vol. 37(7), pages 2807-2813, July.
    15. Boudet, Hilary S. & Flora, June A. & Armel, K. Carrie, 2016. "Clustering household energy-saving behaviours by behavioural attribute," Energy Policy, Elsevier, vol. 92(C), pages 444-454.
    16. Du, Ping & Zheng, Li-Qun & Xie, Bai-Chen & Mahalingam, Arjun, 2014. "Barriers to the adoption of energy-saving technologies in the building sector: A survey study of Jing-jin-tang, China," Energy Policy, Elsevier, vol. 75(C), pages 206-216.
    17. Lei, Jiawei & Yang, Jinglei & Yang, En-Hua, 2016. "Energy performance of building envelopes integrated with phase change materials for cooling load reduction in tropical Singapore," Applied Energy, Elsevier, vol. 162(C), pages 207-217.
    18. Berry, Stephen & Davidson, Kathryn, 2016. "Improving the economics of building energy code change: A review of the inputs and assumptions of economic models," Renewable and Sustainable Energy Reviews, Elsevier, vol. 58(C), pages 157-166.
    19. Acosta, Ignacio & Campano, Miguel Ángel & Molina, Juan Francisco, 2016. "Window design in architecture: Analysis of energy savings for lighting and visual comfort in residential spaces," Applied Energy, Elsevier, vol. 168(C), pages 493-506.
    20. de la Rue du Can, Stephane & Leventis, Greg & Phadke, Amol & Gopal, Anand, 2014. "Design of incentive programs for accelerating penetration of energy-efficient appliances," Energy Policy, Elsevier, vol. 72(C), pages 56-66.
    21. Morris, Peter & Vine, Desley & Buys, Laurie, 2015. "Application of a Bayesian Network complex system model to a successful community electricity demand reduction program," Energy, Elsevier, vol. 84(C), pages 63-74.
    22. Steg, Linda, 2008. "Promoting household energy conservation," Energy Policy, Elsevier, vol. 36(12), pages 4449-4453, December.
    23. Kelly, Geoff, 2012. "Sustainability at home: Policy measures for energy-efficient appliances," Renewable and Sustainable Energy Reviews, Elsevier, vol. 16(9), pages 6851-6860.
    24. Newsham, Guy R. & Donnelly, Cara L., 2013. "A model of residential energy end-use in Canada: Using conditional demand analysis to suggest policy options for community energy planners," Energy Policy, Elsevier, vol. 59(C), pages 133-142.
    25. Al-Ghandoor, A. & Jaber, J.O. & Al-Hinti, I. & Mansour, I.M., 2009. "Residential past and future energy consumption: Potential savings and environmental impact," Renewable and Sustainable Energy Reviews, Elsevier, vol. 13(6-7), pages 1262-1274, August.
    26. De Boeck, L. & Verbeke, S. & Audenaert, A. & De Mesmaeker, L., 2015. "Improving the energy performance of residential buildings: A literature review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 52(C), pages 960-975.
    27. Chen, Victor L. & Delmas, Magali A. & Kaiser, William J. & Locke, Stephen L., 2015. "What can we learn from high-frequency appliance-level energy metering? Results from a field experiment," Energy Policy, Elsevier, vol. 77(C), pages 164-175.
    28. Young, Denise, 2008. "When do energy-efficient appliances generate energy savings? Some evidence from Canada," Energy Policy, Elsevier, vol. 36(1), pages 34-46, January.
    29. Linden, Anna-Lisa & Carlsson-Kanyama, Annika & Eriksson, Bjorn, 2006. "Efficient and inefficient aspects of residential energy behaviour: What are the policy instruments for change?," Energy Policy, Elsevier, vol. 34(14), pages 1918-1927, September.
    30. Pacheco, R. & Ordóñez, J. & Martínez, G., 2012. "Energy efficient design of building: A review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 16(6), pages 3559-3573.
    31. Chen, Xi & Yang, Hongxing & Lu, Lin, 2015. "A comprehensive review on passive design approaches in green building rating tools," Renewable and Sustainable Energy Reviews, Elsevier, vol. 50(C), pages 1425-1436.
    32. Yamamoto, Yoshihiro & Suzuki, Akihiko & Fuwa, Yasuhiro & Sato, Tomohiro, 2008. "Decision-making in electrical appliance use in the home," Energy Policy, Elsevier, vol. 36(5), pages 1679-1686, May.
    33. Mills, Bradford & Schleich, Joachim, 2012. "Residential energy-efficient technology adoption, energy conservation, knowledge, and attitudes: An analysis of European countries," Energy Policy, Elsevier, vol. 49(C), pages 616-628.
    34. Fercovic, Juan & Gulati, Sumeet, 2016. "Comparing household greenhouse gas emissions across Canadian cities," Regional Science and Urban Economics, Elsevier, vol. 60(C), pages 96-111.
    35. Bradley, Peter & Coke, Alexia & Leach, Matthew, 2016. "Financial incentive approaches for reducing peak electricity demand, experience from pilot trials with a UK energy provider," Energy Policy, Elsevier, vol. 98(C), pages 108-120.
    36. Trevor S.K. Ng & Raymond M.H. Yau & Tony N.T. Lam & Vincent S.Y. Cheng, 2016. "Design and commission a zero-carbon building for hot and humid climate," International Journal of Low-Carbon Technologies, Oxford University Press, vol. 11(2), pages 222-234.
    37. Kim, Hyung Chul & Keoleian, Gregory A. & Horie, Yuhta A., 2006. "Optimal household refrigerator replacement policy for life cycle energy, greenhouse gas emissions, and cost," Energy Policy, Elsevier, vol. 34(15), pages 2310-2323, October.
    38. Rae, Callum & Bradley, Fiona, 2012. "Energy autonomy in sustainable communities—A review of key issues," Renewable and Sustainable Energy Reviews, Elsevier, vol. 16(9), pages 6497-6506.
    39. Kenisarin, Murat & Mahkamov, Khamid, 2016. "Passive thermal control in residential buildings using phase change materials," Renewable and Sustainable Energy Reviews, Elsevier, vol. 55(C), pages 371-398.
    40. Carlsson-Kanyama, Annika & Linden, Anna-Lisa, 2007. "Energy efficiency in residences--Challenges for women and men in the North," Energy Policy, Elsevier, vol. 35(4), pages 2163-2172, April.
    41. Neves, Diana & Silva, Carlos A. & Connors, Stephen, 2014. "Design and implementation of hybrid renewable energy systems on micro-communities: A review on case studies," Renewable and Sustainable Energy Reviews, Elsevier, vol. 31(C), pages 935-946.
    42. Swan, Lukas G. & Ugursal, V. Ismet, 2009. "Modeling of end-use energy consumption in the residential sector: A review of modeling techniques," Renewable and Sustainable Energy Reviews, Elsevier, vol. 13(8), pages 1819-1835, October.
    43. St. Denis, Genevieve & Parker, Paul, 2009. "Community energy planning in Canada: The role of renewable energy," Renewable and Sustainable Energy Reviews, Elsevier, vol. 13(8), pages 2088-2095, October.
    44. Campillo, Javier & Dahlquist, Erik & Wallin, Fredrik & Vassileva, Iana, 2016. "Is real-time electricity pricing suitable for residential users without demand-side management?," Energy, Elsevier, vol. 109(C), pages 310-325.
    45. Filippini, Massimo & Hunt, Lester C. & Zorić, Jelena, 2014. "Impact of energy policy instruments on the estimated level of underlying energy efficiency in the EU residential sector," Energy Policy, Elsevier, vol. 69(C), pages 73-81.
    46. Ruparathna, Rajeev & Hewage, Kasun & Sadiq, Rehan, 2016. "Improving the energy efficiency of the existing building stock: A critical review of commercial and institutional buildings," Renewable and Sustainable Energy Reviews, Elsevier, vol. 53(C), pages 1032-1045.
    47. Strbac, Goran, 2008. "Demand side management: Benefits and challenges," Energy Policy, Elsevier, vol. 36(12), pages 4419-4426, December.
    48. Timmons, David & Konstantinidis, Charalampos & Shapiro, Andrew M. & Wilson, Alex, 2016. "Decarbonizing residential building energy: A cost-effective approach," Energy Policy, Elsevier, vol. 92(C), pages 382-392.
    49. Gaspar, Rui & Antunes, Dalila, 2011. "Energy efficiency and appliance purchases in Europe: Consumer profiles and choice determinants," Energy Policy, Elsevier, vol. 39(11), pages 7335-7346.
    50. Nejat, Payam & Jomehzadeh, Fatemeh & Taheri, Mohammad Mahdi & Gohari, Mohammad & Abd. Majid, Muhd Zaimi, 2015. "A global review of energy consumption, CO2 emissions and policy in the residential sector (with an overview of the top ten CO2 emitting countries)," Renewable and Sustainable Energy Reviews, Elsevier, vol. 43(C), pages 843-862.
    51. Florides, G. A. & Tassou, S. A. & Kalogirou, S. A. & Wrobel, L. C., 2002. "Measures used to lower building energy consumption and their cost effectiveness," Applied Energy, Elsevier, vol. 73(3-4), pages 299-328, November.
    52. Heier, Johan & Bales, Chris & Martin, Viktoria, 2015. "Combining thermal energy storage with buildings – a review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 42(C), pages 1305-1325.
    53. Vine, Edward & du Pont, Peter & Waide, Paul, 2001. "Evaluating the impact of appliance efficiency labeling programs and standards: process, impact, and market transformation evaluations," Energy, Elsevier, vol. 26(11), pages 1041-1059.
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