By Nidhi DhullReviewed by Susha Cheriyedath, M.Sc.Jun 5 2024The construction sector is a major contributor to the current climate and energy crises. High living standards and digitalization are further increasing the energy demand in buildings. Thus, the transition toward sustainability and greening of the construction sector requires integrating renewable energy systems into buildings.1,2
Image Credit: jantsarik/Shutterstock
Different renewable energy sources, such as solar, wind, geothermal, and biomass, can be incorporated into buildings in numerous forms according to the location and policy support. These can make buildings self-sufficient and carbon-neutral and lower long-term operational costs.1 This article explores various renewable energy systems for green buildings and their contribution to sustainability.
Renewable Energy Systems for Green Buildings
Buildings utilize energy for various reasons throughout their life cycle, over 90 % of which is used for heating/ventilation/air conditioning (HVAC) systems during the operational phase. Thus, integrating active and passive renewable energy systems for HVAC can significantly mitigate the carbon footprint of the construction sector.2
Solar energy is actively used in buildings as photovoltaics, solar power generation, and solar hot water systems. Alternatively, building positioning, airflow, and thermal biomass are passive systems used in buildings. Solar technology integrated with windows can control temperature and insulation, improving the comfort of occupants while saving energy.1,2
Wind energy is also being widely applied in the building sector with the advancement of offshore systems. Power generation, ventilation, and impedance design technologies are commonly employed in buildings.1 While wind catchers help cool the building with natural ventilation, thermal chimneys draw in fresh air from outside.2
Geothermal energy is a constant renewable energy source, independent of external conditions like climate or time of day.1 It is used for heating and cooling in houses, greenhouses, and agriculture through heat pumps, in-well heat exchangers, and pipes.2
Similarly, biomass from organic materials produces energy through aerobic/anaerobic digestion. It is generally utilized as a biomaterial in the construction of building parts to reduce the consumption of fossil fuels and emissions.1 Additionally, biomass sources from within the buildings can be exploited to produce electricity using dedicated power plants.1,2
Contribution to Sustainability
Different renewable energy sources each have a unique contribution towards making buildings more sustainable. Of the total energy consumption in buildings worldwide, 17 % is allocated for lighting. Proper architectural design can harness up to 70 % of this lighting requirement directly from sunlight. Furthermore, incorporating solar energy and photovoltaic technologies can increase a building's renewable energy use to 83 %, while reducing overall energy demands by 48%. Wind energy also plays a critical role in reducing carbon emissions and the use of non-renewable energy.
As of 2017, wind power has helped stop over 600 million tons of greenhouse gas emissions. Additionally, wind energy systems installed on construction sites can supply up to 15 % of a building’s energy needs.1
Geothermal energy systems can enhance the energy efficiency of buildings while minimizing energy expenses and GHG emissions. Moreover, they function quietly, eliminating the noise of conventional HVAC systems and improving residents’ comfort and health. Simultaneously, the relatively small land area requirement of geothermal systems is ideal for urban landscapes with limited space.1
Biomass-derived energy can also significantly reduce non-renewable energy usage (up to 93 %) and CO2 emissions (up to 94 %). Additionally, utilizing wood chips and pellets as fuel in biomass boilers rather than diesel can decrease up to 40000 tons of CO2.1
For more on sustainability in construction, check out this article!
Challenges
While beneficial, incorporating renewable energy into buildings encounters several challenges. For instance, the inconsistency of solar energy supply complicates the integration of photovoltaic air collectors. Additionally, the design of these systems must consider the building’s structural load-bearing capacity. Regular maintenance and the need for periodic component replacement in photovoltaic systems also increase the overall maintenance costs of buildings.1
Wind and geothermal energy generation technologies entail substantial costs for manufacturing, installation, and maintenance. Wind energy efficiency depends on natural wind speeds and the specific layout of the building, while the effectiveness of geothermal systems hinges on the geological characteristics of the site. Additionally, noise from operating wind turbines can pose problems for the surrounding area.1
Biomass, primarily derived from agricultural waste, poses another set of challenges. Uncontrolled extraction for energy purposes can lead to significant vegetation destruction, making it difficult to ensure a steady supply of biomass for large-scale construction projects. Furthermore, biomass materials are vulnerable to environmental factors like moisture, pests, and fire, necessitating additional treatments and protective measures to maintain the integrity of biomass-based systems.1
Despite some governmental financial incentives for integrating renewable energy into buildings, these aids are often insufficient to offset the significantly higher costs compared to traditional energy sources. Moreover, frequent changes in policies and regulatory uncertainties discourage investors and developers from committing to renewable energy projects.1
Latest Developments
Recent developments have brought innovative approaches to bolstering the energy sustainability of modern infrastructure. For example, a study highlighted in Sustainable Energy Technologies and Assessments introduces an artificial intelligence-based technique for monitoring systems in smart buildings. This system predicts energy usage and renewable energy requirements and evaluates recycling efforts. It presents a more precise and effective solution to the growing challenges in managing energy within smart cities compared to traditional methods.3
Another study published in Energies explored the concept of Virtual Power Plants (VPPs), which integrate renewable energy generation and storage to create a sustainable, controllable power grid. VPPs effectively manage the power output from distributed energy resources (DERs) and coordinate load consumption. They also enable participation in energy markets, facilitating energy trading and sharing. This contributes to the self-scheduling of renewable sources and demand-side frequency control, showcasing the potential for a stable and efficient renewable energy management system.4
Future Prospects
Looking forward, renewable energy-integrated buildings are vital in modern urban development strategies aimed at reducing the building sector’s impact on climate change and energy crises.2 Future cities will require smart technological resources for intelligent management of heating, cooling, and lighting while promoting energy sharing within the community. This can be achieved through financial incentives, market transformation, and robust renewable energy policies.
Additionally, the challenges posed by individual renewable energy systems can be addressed by employing hybrid systems. Optimizing these hybrid systems with machine learning and artificial intelligence can enhance their feasibility and long-term functionality. These innovations in renewable energy are key to achieving sustainable buildings that embrace intelligence, diversity, and digitization.1
References and Further Reading
1. Chen, L. et al. (2023). Green building practices to integrate renewable energy in the construction sector: a review. Environmental Chemistry Letters, 22. https://doi.org/10.1007/s10311-023-01675-2
2. Yüksek, İ., & Karadağ, İ. (2021). Use of Renewable Energy in Buildings. Renewable Energy - Technologies and Applications. https://doi.org/10.5772/intechopen.93571
3. Selvaraj, R., Kuthadi, V. M., & Baskar, S. (2023). Smart building energy management and monitoring system based on artificial intelligence in smart city. Sustainable Energy Technologies and Assessments, 56, 103090. https://doi.org/10.1016/j.seta.2023.103090
4. Liu, J., Hu, H., Yu, S. S., & Trinh, H. (2023). Virtual Power Plant with Renewable Energy Sources and Energy Storage Systems for Sustainable Power Grid-Formation, Control Techniques and Demand Response. Energies, 16(9), 3705. https://doi.org/10.3390/en16093705
Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.