When trying to improve HVAC operation, many FMs have taken on metering electricity use to tell how efficiently HVAC equipment is working. While helpful, this practice only tells part of the story.
“For a lot of facilities managers, if you asked them, ‘How does your HVAC equipment – your chiller or boiler plant, as examples – behave on a 60-degree day without humidity?’ or ‘How do they behave on an 80-degree day with high humidity?’ I think a lot of the time the answer is that the data isn’t really available,” says Mark Pando, Energy Project Engineer at Enertiv, a provider of IoT solutions for commercial real estate portfolios. “IoT solutions can tie in with local weather data to fill in that picture for a lot of facilities managers in terms of their equipment today, as well as last week and last month.”
By implementing this dataset into daily operations, you can improve efficiency, maintenance and overall preparedness for your building’s HVAC systems. Here are four ways leveraging local weather data can improve your facility.
1) More Efficient HVAC Operation
The most obvious improvement local weather data presents is improving energy efficiency in HVAC systems. Because it helps systems adjust more precisely to current and changing conditions, you can save significantly on heating and cooling costs with users often reaching 5-15% in energy savings for HVAC systems.
“We deploy sensors on the electrical infrastructure in the building to measure the real-time equipment-level consumption of the individual components in the HVAC system,” says Pando. “Whether that’s a pump, an individual fan or a cooling tower, we deploy sensors to collect that equipment-level data and we tie that with local weather data through our software. We can leverage those two data streams together to deliver these insights.”
Based on the amalgamation of data, you can then adjust your equipment to better account for changes in the weather. As temperatures begin to dip in the autumn and rise in the spring, you can account for environmental shifts more accurately and in a more timely fashion, which can be especially lucrative in areas where weather fluctuations are more extreme.
“In terms of geographical areas, it is definitely beneficial everywhere, but for places that have more seasonality and greater temperature swings, it can be more useful,” says Pando. “You have more opportunities to intervene where the controls may be set to handle cool or cold weather and then the weather turns out to be warm and the setpoints, the system or the facilities team might not be ready. The system may not be set up to handle that kind of faster change in local weather conditions.”
2) Simpler HVAC Maintenance
Understanding your HVAC efficiency with more detail can also improve your maintenance practices. By incorporating local weather data with equipment data, you can identify peak operation and, perhaps more importantly, when equipment is not adequately performing.
“Assuming things are in relatively good shape, you can then use that data as a baseline looking forward,” explains Pando. “If tomorrow’s forecast is a 60-degree day with low humidity, you can see how the equipment should behave and drive maintenance decisions based around whether or not that piece of equipment behaves within the predicted amounts.”
Pando describes how by tying equipment data and weather data into a prediction model, you can more easily identify problems. For example, if a system is supposed to be drawing 100 kW of power but is for some reason drawing above or below that, it becomes easier to pinpoint what is wrong and you can quickly resolve the problem.
“One example would be to identify when an air-side economizer might not be working in the right weather conditions. If the temperatures are in the area where free cooling via air-side economizers is possible and should be occurring but the data coming from IoT sensors for equipment shows that the economizers are not operating, that’s a great opportunity to use data to identify what the problem is,” explains Pando. “You can mobilize resources to take care of that problem as soon as possible rather than waiting for the next service call.”
3) Better Response to Local Weather Events
In addition to its more direct contributions to HVAC systems, using IoT sensors for weather data can help you prepare for other events that might require your attention. Most sensors pull multiple data points such as temperature, wind speed, humidity, cloud coverage and precipitation.
The data for precipitation can prove particularly valuable to protect your building against flood damage. When local weather data suggests prolonged rain, it can tip you off to possible flooding and give you time to shore up your building’s defenses against it.
In one application, Pando recalls how one building using local weather data was able to notify the facilities staff early enough about the flood potential, which gave them the opportunity to save important equipment and electrical systems. With this warning, the facilities staff was able to prevent any major damage in the basement, which would have otherwise added up to thousands of dollars.
4) Easier Retrofits in the Future
Although it might not be on your mind during implementation, using local weather data can help you simplify the retrofitting process in the future.
As sensors pick up and synthesize equipment and weather data, you have a complete story of operation and efficiency with your current equipment. You will know what works best for what systems under any number of conditions. You can use this information when looking for new HVAC equipment.
“Having very detailed data about how different pieces of equipment have performed in the past can be very instrumental to potential retrofits in the future,” says Pando. “A lot of times, retrofit decisions are based on energy auditors’ best practices, but rarely do they have a holistic view of how something behaves over an entire heating or cooling season. Having that very rich dataset, especially when paired with local weather data, can be instrumental when identifying oversights with it.”
Justin Feit [email protected] is Associate Editor of BUILDINGS.
