Solar PV and wind supply about 40% of building electricity use by 2030

Expanding the share of electricity in buildings’ final energy consumption is a key milestone to reach in the Net Zero Emissions by 2050 Scenario (NZE Scenario), which sees solar and wind supply used in electricity generation rise from 9% in 2020 to 40% in 2030. The gains will be underpinned by increased electrification of space heating and hot water generation, and the growing demand for space cooling and electrical appliances. Driven by technology cost reductions, policy support and technology maturity, the share of solar PV and wind in electricity generation will reach 68% by 2050 in the NZE Scenario.

To bridge the gap between variable renewable energy production and time of use, the inclusion of electrical and thermal (power-to-heat by electrically-driven heat pumps) energy storage as well as flexibility mechanisms like dynamic pricing and smart home controls is required. By 2030, buildings increasingly become a source of flexibility for the energy system, enabling efficient coupling of variable PV and wind with the use of electricity for building purposes (e.g. heating/cooling). Bidirectional charging of electrical vehicles can be facilitated by flexibility in smart grids and energy storage, either in the form of batteries (also car batteries) or thermal storage (hot and cold storage). In combination with economic drivers, flexibility and energy storage deployed in smart buildings are expected to further advance energy conscious behaviour and uptake at the consumer and commercial levels.

Reaching 40% of the building sector’s electricity demand by wind and PV goes hand in hand with a transformation of energy demand in buildings. While current wind and PV production can be absorbed by the building demand, increased electricity generation from variable renewables and the design of energy systems at the building and district level will need to be adopted. In the context of shifting and growing electricity consumption profiles for heating, cooling and appliances, as well as higher demand due to electric vehicles (EVs), energy storage solutions within buildings integrating smart/automatised controls will be required to further increase the share of renewable electricity to over 40% and contribute to a more resilient energy system.

On-site and district level solar PV installations are an easy option to decarbonise the energy supply and to increase the deployment of nearby renewable production. Balancing demand (including heating/cooling which account for the majority of energy demand) close to energy supply will reduce costs induced by congestion, distribution or fees of grid operators.

A substantial part of building-level PV is generated when it is not needed. Self-consumption can be increased by demand response of smart appliances whose use can be shifted to times of high PV production and storage (including bidirectional EV charging). Storage options can be electrical, but also thermal enhanced by heat pumps or chillers. In some cases, excess electricity can be stored in local (neighbourhood) storages that should be used in a coordinated way among buildings for short-term or even seasonal periods.

Energy storage solutions are a mass-market technology for a number of applications in many parts of the world. The costs per energy storage unit for an average building are easing due to technological developments, innovation, and economies of scale. With rising prices of fossil fuels and CO₂ allowances, the competitive advantage of decarbonised solutions becomes more favourable. For emerging markets, investments in grid infrastructure can be reduced by deploying energy storage technologies.

Emerging smart building and smart grid solutions include appliances that trigger on injections to the grid to start or increase consumption. Building energy management systems that coordinate multiple smart appliances, storage and communicate with other buildings and grid stakeholders to ensure grid-secure flex activations are also evolving.

Not only is electrification of building end-uses progressing, but the evolution in computing and forecasting technologies, such as widespread instrumentation and advanced computer models, among others, allow for better response to intermittency issues of renewable energy sources (RES). This is further supported by demand-side response technology advances (smart meters coupled with intelligent appliances such as heat pumps, air conditioners, and white goods) and increasing deployment of smart inverters (inverters and power electronics that can provide grid support and control to system operators). Lastly, real-time system awareness and management solutions (instrumentation and control equipment across transmission and distributions networks) enable system operators to actively manage grid behaviour.

Although operational costs could become very competitive compared to traditional systems, upfront capital costs are limiting access to emerging smart solutions. Aside from the initial costs, comfort and ease of operation are expected to help speed up users’ acceptance.

To promote the integration of energy storage technologies, solving some physical adaptations will be required, including reducing the size of storage systems by increasing their energy density. In terms of system integration, emphasis should be placed on interoperability of different technologies when coupling various load patterns like heating/cooling, and EV charging at the building level. Building energy management systems that take frequent automated actions based on flexible time-of-use pricing structures are not widespread and should be accelerated. Nevertheless, the coordinated actions among management systems will be required to mitigate the risk stemming from overreactions to market signals.

Even though the variability of electricity generation is increasing, reaching this milestone must go in tandem with ensuring power system reliability. Traditional electricity infrastructure networks need to become dynamic to facilitate the non-dispatchable renewable energy production with load patterns and more variable electricity demand. 

• Cost reductions at component and system level supporting new business models where flexibility and energy storage leads to creating economic value.
• Develop standardised Plug and Play solutions and simple system design tools.
• Improving the compactness of energy storage technologies to better integrate energy storage in buildings.
• Availability, quality, and security of energy data, open-source models of energy storage systems, and smart control algorithms maximising the use of PV and wind energy in buildings without causing grid problems.
• System integration aspects including smart control of building integrated PV, heat pumps, energy storage, and bidirectional charging systems for electric vehicles. Also system solutions for energy communities and positive energy districts, including central or decentralised technologies.
• Investigating social dimensions of user engagement with automated technologies in energy systems to understand how end-user trust to automate is built and maintained.
• Understanding policy, regulatory, social and technological conditions necessary to support the wider deployment of peer-to-peer, community self-consumption and transactive energy models.
• Energy flexibility of buildings in future energy systems to increase the uptake of renewables and related business cases.