Integrating weather data into smart building management systems can save energy, improve the indoor environment and reduce climate impact
Over the past nine months, we’ve been working with BIM Today looking at the importance of applying weather and climate data in the design and construction of buildings.
However, it’s not just these two phases of the build where weather data can help improve safety, efficiency, day-to-day facilities management and the impact on the environment.
Existing buildings can benefit from integrating weather data into various smart building management systems, with energy savings, quality of the indoor environment and reduced impact on our climate being the most important gains.
Changes in our climate – hotter, drier summers and warmer, wetter winters – bring challenges for building managers. Ensuring optimal thermal comfort of occupants and minimising energy use required by net-zero policies is a balancing act.
In recent years, new concepts and technologies have been in constant development. Engineers and researches worldwide are in search for intelligent building management methods. Methods to help improve energy efficiency and sustainability in buildings. But a pleasant indoor environment for the occupants must not be compromised.
Weather and climate data play an important part in this process.
Achieving net-zero
Achieving net-zero emissions by 2050 is now enshrined in law. Many built and natural environment professions have declared a commitment to achieve this.
According to UN 2019 Global Status Report for Buildings and Construction Sector, buildings are one of the highest consumers of energy overall and one of the top contributors to climate change. Globally, building operations account for about 28% of emissions annually.
Emma Stewart, report co-author and director of urban efficiency and climate at WRI Ross Centre for Sustainable Cities, is cited as saying: “If you’re interested in tackling climate change, buildings are the single most cost-effective place to start”. It is crucial for the industry to look at the best ways to decarbonise.
The first step in addressing emissions should be reducing consumption through energy-efficient design and day-to-day operation of buildings. The next is replacing fossil fuels with on- or offsite renewable energy systems.
The majority of building-related carbon emissions come from energy use for heating, cooling, ventilation and lighting. Most of the energy in buildings is used to maintain thermal comfort and air quality. Optimal control of HVAC (Heating, Ventilation and Air Conditioning) in existing buildings is therefore essential for effective energy use and reduced carbon footprint. An energy-efficient building could be a brand-new structure or an existing one retrofitted with new BMS, BEM or other smart building management systems for optimised heating, cooling, and lighting.
Various organisations in the sector are calling on the government to regulate the operational performance of buildings. They emphasise the need for a regulatory framework covering energy consumption, carbon emissions, climate resilience and quality of indoor environment.
Decarbonising the economy is reliant on effective policy and economics, developments in technology and a shift in people’s attitudes and behaviour. The sector is challenged to come up with innovative ideas to build new and change existing buildings to ensure they are resilient in tomorrow’s world.
It is vital that the future of construction considers short-term weather and long-term climate challenges within BIM for design and build and BEM for ongoing energy use to mitigate our effects on climate change, one building at a time.
The role of the weather in creating ‘smarter’ energy-efficient buildings
Weather is one of the main factors that impact indoor conditions and resulting energy use.
External temperature, wind, humidity, pressure and sunshine all impact thermal conditions, air quality, use of water and amount of natural light in a building. There’s a direct relationship between a building’s day-to-day operations, energy needs and the weather conditions.
BEM systems, digital twins and any type of real-time building management systems can be much more efficient with integrated weather data. Weather forecasts allow a building to react with heating, cooling, ventilation, water use and lighting by foreseeing changes in the weather before they occur. In doing so, we can prevent hot radiators being left on throughout the summer or lights being left on when there’s enough natural light. It allows a building to decide when these resources are needed.
Weather data can also enable efficient use of renewables such as solar panels or water harvesting systems. Sophisticated software can make intelligent decisions on when to switch to solar energy, which part of the building to shade with sunshades and when to use water from tanks.
Energy modelling of residential and commercial buildings has gained importance in recent years. Accurate weather data plays an important role in this process. Dynamic energy simulations are impossible without localised, hourly data of weather conditions like solar radiation, temperature, humidity, atmospheric pressure, and wind speed and direction.
Another application of weather data in intelligent building management is model-predictive control (MPC). It uses real-time information about building occupancy and use, weather forecasts, and sometimes price signals from the grid to control heating, cooling, ventilation and air conditioning. The system feeds this real-time information into a model to evaluate control strategies. This can be for the next hours or days, re-evaluating as new information or forecasts come in. In short, using weather data MPC anticipates the energy needs of the building and optimises its thermal behaviour.
One example of a building using the model predictive control is 3E Headquarters in Brussels. The MPC method was able to reduce the energy costs by more than 30% while still providing thermal comfort to occupants.
BestData for optimised building performance
Dynamic building management with integrated weather data is becoming increasingly necessary for achieving energy savings in existing buildings. Control and optimisation of HVAC, lightning and renewable energy systems are significant components of energy-efficiency in buildings. When running completed buildings, problems tend to occur when there is no direct relationship between a building’s operations and the weather conditions. Met Office BestData data provides that link and allows a building to react to heating, cooling, and lighting by anticipating changes in the weather before they occur.
Met Office BestData uses a blend of weather models to provide forecast data to any location in the UK. By measuring weather data at the building location, we capture the building’s microclimate. These site-specific forecasts update hourly and can be delivered in a simple CSV format via email or FTP. They include a range of parameters such as temperature, humidity, sunshine hours and solar radiation, rain and wind.
Sunshine is arguably the most important factor to the heating and cooling of a building. BestData provides forecasts of Instantaneous and Integrated Direct Downward radiation, as well as Instantaneous and Integrated Diffuse Downward radiation. “Instantaneous” measures the power in watts per m2 at the time and “Integrated” is the energy per m2 over the previous hour expressed in kWh. “Direct” is the power obtained directly from the sun, while “Indirect” is the light energy, except that obtained directly from the sun.
Conclusion
With the advancement of BIM, other BMSs for facilities management and the accuracy of internal building sensors, the potential for aligning a building’s operational behavior with that of its external surroundings has never been greater.
The short-term advantages of understanding energy use like this is the ability to save money on heating and cooling. Those who manage buildings should be able to boast that they can react to the weather, the same way people do – by simply planning.
The longer-term advantages of understanding energy use in the context of the future climate, enable infrastructure to become more resilient and sustainable. Weather and climate information can help the sector meet the usage demands of today and prepare for changes in the future.
For further information please contact our Construction Team at construction@metoffice.gov.uk, or visit our construction page.
Tel: 0370 900 0100
www.metoffice.gov.uk/construction
Please note: this is a commercial profile.
