Shoulder seasons feel fantastic. Cool mornings give way to crisp and pleasant daytime warmth, which finally cedes its ground again to the refreshing nighttime.
As soon as spring starts, we start our air conditioner each night. It has no moving parts. It is free. For the most part it is totally silent, although each morning at dawn it chirps and tweets until someone gets out of bed and slams it shut.
Yes, a window at night is all the cooling we need to bring down the thermal mass of our home to stave off afternoon warmth.
Depending on where you live, you probably have a similar way of managing temperature in your home without starting either the heating or cooling systems. Many of the same tricks can be used in buildings during shoulder seasons to minimize energy consumption and those pesky demand charges.
For example, spring is a great season for pre-cooling, the technical equivalent of opening a window at night. Economizing dampers have a wide operating range and can let lots of cool air into the building to ensure the thermal mass is cool before opening hours. This can help reduce the impact of that warm afternoon and allow the facility to coast all the way through a warm afternoon without starting a chiller.
If you are worried about a particular day, Gridium’s Snapmeter tool provides five day ahead weather and energy forecasts, tracks your current demand charge and let’s you know if you’re going to trigger a demand charge on a warm afternoon. If that’s the case, you might want to get more aggressive with pre-cooling and even start a chiller earlier to get ahead of cooling needs. Because of electric rate structures, it almost always makes sense to get cold water flowing through the system before you need it rather than reacting to suddenly warm return air.
Spring is also a great chance to check your heating systems. Many teams can lower water temperatures, check outside air resets and check air and lighting start times for summer schedules.
2014 was the warmest year in the last 135. Maybe 2015 will be worse? For now, enjoy the nice weather and for once, let mother nature do a little bit of the work in the building.