As a building manager, you’re likely familiar with the savings and benefits fully automated building functions can bring to your property. Today’s highly integrated building automation systems (BAS) link multiple sensors with systems control equipment to optimize heating, cooling, and ventilation, delivering savings on energy, maintenance, and longer equipment life.
No matter how sophisticated your control equipment is, your BAS’s ability to react to ever-changing weather conditions is limited by the quality of data about environmental conditions that your system can access.
While sensors provide minute-by-minute information about local environmental conditions, building automation systems increasingly rely on third-party weather forecasts to fine-tune operations and optimize savings.
In this blog, we uncover how BASs access and utilize independent weather forecasting data, and how building managers play a central role in which sources of information your system can access. Read on to learn more.
How Does Your BAS Use Weather Forecasts?
Building automation systems are designed to optimize the performance of your building’s critical systems by allowing these to adjust to match both the needs of users and the prevailing environmental conditions.
To do this, your BAS needs access to inputs from a wide range of sensors, including temperature, sunlight, wind speed, humidity, and precipitation. These metrics allow the system to adjust systems in real-time, for example by adjusting lighting when cloud cover builds, or boosting room temperatures when falling humidity makes interiors feel colder.
Advanced systems, however, also rely increasingly on data from third-party weather forecasting services to power their more sophisticated automated decision-making. There are two major reasons for this:
- Historical data and day-to-day forecasts offer a moving “baseline” for your system’s key performance parameters. For example, knowing exactly how hot a given month (or week) has been in the past and how hot professional forecasters expect it to be in the future allows you to predict energy demand and adjust your system in advance.
- Weather forecasts provide a longer “event horizon”, giving your system more time to react to expected changes. This can lead to significant energy savings. For example, if a heatwave is predicted, your BAS will know to pre-cool the building during the cooler night hours, reducing the load on your system during peak daytime temperatures.
Let’s take a closer look at the types of predictive information these smart BAS systems require.
Key Sources of Predictive Data for BASs
To respond effectively, your BAS needs access to good-quality numerical, benchmarked data that captures usable information about environmental conditions. These include
- Temperature — including both historical and expected temperatures and the expected range of variation.
- Wind speed and direction — are both essential to calculating chill factors and “feels like” temperatures.
- Precipitation — useful to predict likely cloud cover, as well as for managing rainwater harvesting systems.
- Humidity — critical to adjusting internal temperatures to comfortable levels.
- Barometric pressure — useful in predicting temperature, cloud cover, wind speed and direction, precipitation, and rainfall.
How Does Your BAS Use Weather Data?
Increasingly smart BAS systems use information from weather forecasts in ever-more sophisticated ways. Here are just a few ways that good quality weather data can be put to use.
- To smooth out energy spikes — With reliable information about temperature swings for days in advance, systems can adjust sooner to limit high-demand events.
- To prepare for extreme events — Early preparation matters when it comes to blizzards, high-rainfall events, and record-setting heat waves. At times like this, working off historical averages will not work.
- To manage precipitation and rainwater harvesting — Many smart buildings now include rainwater harvesting to reduce water usage. Reliable information about rainfall can help plan how collected rainwater should be used.
- To adjust shading — Automated window shades can be moved into or out of position depending on expected conditions.
- To plan predictive maintenance — Schedule maintenance based on how hard you expect heating and cooling systems to work in the days and weeks ahead. Schedule downtime for milder days to maintain comfort levels.
- To predict likely energy demand — Compare subtle changes in heating and cooling demand with previous years’ weather records to predict future HVAC requirements.
How Do BAS Systems Access Weather Data?
Real-time weather forecasting data is now widely available from many vendors. Typically, your BAS will access data through a purpose-designed application programming interface (API) that allows your system to connect to cloud-based services or other providers.
Weather data is provided by several large vendors including CustomWeather, AWIS Weather Services, and Meteosource. In the U.S. many vendors make use of publicly available weather data provided by the National Weather Service.
The specific weather service your BAS utilizes depends on which system you use. Value-based equipment may come with a weather data vendor preset, while more advanced controllers will combine information from several sources, and may even allow building managers to choose which vendor their BAS uses — and update it as needs change.
How Much Weather Data Do You Need?
Smart, open-source BAS equipment makes it easier than ever to connect equipment to cloud services like weather data. That can equate to real gains in performance for your system, but it can also mean spending money on functionality you don’t really need.
At MACC, we are experts at matching BAS technology to your budget and real-world requirements. We’re ready to hook you up with fully integrated, leading-brand BAS systems that play nicely with your existing automation infrastructure and connect seamlessly with cloud services like weather data vendors.
We support all our installations from concept through to commissioning and offer ongoing maintenance and training services too.
Click below for a free consultation, and discover how MACC can help you make the BAS connections your building needs.
