Session 19: Energy flexibility & Demand side management
10:30am - 10:45am
Empowering energy flexibility and climate resilience using collective intelligence based demand side management (CI-DSM)
1Lund University, Sweden; 2NTNU, Norway
This work investigates the effectiveness of Collective intelligence (CI) in demand side management (DSM) in urban areas to cope with extreme climate events. CI is a form of distributed intelligence that emerges in collaborative problem solving and decision making. It is used to control the energy performance of buildings in an urban area in Stockholm, through developing CI-DSM and setting certain adaptation measures, including phase shifting in HVAS systems and building appliances. CI-DSM is developed based on a simple communication strategy among buildings, using forward (1) and backward (0) signals, corresponding to applying and disapplying the adaptation measures. Three timescales of 15 min, 30min and 60 min are tried for the communication between system agents. The performance of CI-DSM is simulated for three climate scenarios representing typical, extreme cold and extreme warm years in Stockholm. Two key performance indicators are used to assess the performance of CI-DSM in reducing energy demand and absorbing shocks due to extreme events, defined as Demand Flexibility Factor (DFF) and Agility Factor (AF). According to the results, CI-DSM increases the autonomy and agility of the system in responding to climate shocks without the need for computationally extensive central decision making systems. CI helps to gradually and effectively decrease the energy demand and absorb the shock during extreme climate events. Having a finer control timescale increases the flexibility and agility on the demand side, resulting in a faster adaptation to climate variations, shorter engagement of buildings, faster return to normal conditions and consequently a higher climate resilience.
10:45am - 11:00am
Towards net-zero carbon performance: using demand side management and a low carbon grid to reduce operational carbon emissions in a UK public office
1University College London, United Kingdom; 2Technical University of Munich, Germany
An important component of energy policy is decarbonisation of national and regional power grids. The reduction in the carbon intensity of the UK national grid over the recent years has important implications for building services and energy performance of buildings. Energy flexibility in buildings is becoming increasingly relevant. The capacity to change a building’s energy consumption profile allows buildings to adapt to variable renewable sources, energy tariffs and user requirements. This offers the possibility for achieving healthy indoor comfort levels at a lower environmental and economic cost. It can transform buildings from passive consumers to active components within the energy sector, in order to support the power grid to balance electrical loads and contribute to the decarbonisation of the energy system. Taking advantage of the existing thermal mass of buildings as an energy storage medium offers the possibility to operate their thermal systems in a variable manner, while maintaining indoor temperatures within a specific comfort range.
This paper aims to explore the concept of energy flexibility in non-domestic buildings using a case study approach. The case study is a low-energy office building that was subject to energy performance contracting and Soft Landings following completion. In addition to identification of energy efficiency improvements at building level, the paper will investigate the potential of this building to achieve net-zero carbon emissions using demand-side management and grid-integration. Key performance metrics such as energy flexibility, energy efficiency and carbon dioxide emissions, and other dependent metrics such as operative indoor temperatures, illuminance levels and energy costs will also be investigated using a building performance model calibrated with the existing performance. The implications of this strategy to deliver net-zero carbon buildings in the UK will be explored based on the projected pathways for the national electricity grid.
11:00am - 11:15am
DEMAND SIDE FLEXIBILITY POTENTIAL AND COMFORT PERFORMANCE OF NON-RESIDENTIAL BUILDINGS
1Process Engineering Design Laboratory, School of Mechanical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; 2Laboratory of Energy Management in the Built Environment, School of Environmental Engineering, Technical University of Crete, 73100 Chania, Greece
The need to create and maintain a sustainable indoor environment is now more than ever compelling. Both the legislation framework concerning the energy performance of buildings, as determined in its evolution through the EU Directives 2010/31/EU, 2012/27/EU and 2018/844/EU, and the European strategic plans towards green buildings, denote the need of sustainability and comfort of indoor environment for the occupant. Moreover, the EU Directive 2018/2001 sets the renewable energy target of at least 32% for 2030, denoting that the high renewable energy sources penetration level leads to challenges in the design and control of power generation, transmission and distribution.
In this line of approach, a possible solution for attaining higher levels of efficiency lies in changing our strategies from traditional supply management, to demand side management of the heating and cooling loads of buildings. Demand side management may be able to provide buildings with the energy flexibility needed, in order to utilize the intermittent production of Renewable Energy Sources in a much more efficient and cost-effective way.
Furthermore, control strategies can be applied in order to utilize the potential of demand side management, as a means of flexibility, yet without jeopardizing the prevailing thermal comfort conditions. In order to achieve this, extra care has to be given on the induction of comfort criteria in order to identify upgraded control strategies.
Main goal of this research approach is to provide a sound understanding of the parameters related to the energy flexibility of non-residential buildings, while introducing mainly applied flexibility metrics. Moreover, the flexibility potential of installed building systems is investigated, while considering the effects on the indoor environment conditions and the perceived comfort. In conclusion, the investigation of demand side flexibility potentials and comfort performance of non-residential can contribute to the improvement of the buildings’ energy efficiency and indoor environment conditions.