What to consider when looking into thermal energy storage

March 17, 2015

Businesses and college campuses alike are always on the lookout for new ways to cut operating costs. Cost-effective heating and cooling is difficult goal to achieve, especially in areas where hot weather puts extra demand on a building's air conditioning system. Thankfully, energy managers can tackle the problem of offsetting these expenses with the help of thermal energy storage. Each facility is unique and will require a personalized solution, but the versatile nature of energy storage makes it easy to integrate storage into the infrastructure of current buildings or incorporate storage technology into a new building's design. Consider the needs of your own facility as you review these important energy storage factors.

Partial vs full load shifting
The New York State Energy Research and Development Authority pointed out that universities and businesses can manage their electricity costs by managing peak energy demand. The resource noted that the period between 2 p.m. and 6 p.m. is when energy consumption is at its highest, electricity is most expensive and utilities across the country scramble to meet peak demand. Buildings.com offers two ways to make that peak management process a little easier.

Partial and full load shifting strategies are both ways that energy storage can be used to limit the expenses that come with consuming electricity during peak demand periods. A partial load strategy involves the building running smaller, rightsized chillers nearly all day and night. During periods of minimal load demand, the extra cooling generated by chillers is stored for later use. When demand approaches peak periods, the chiller can run at the same rate because previously stored cooling is used to help the chiller meet demand during the hottest part of the day. This strategy is also known as "load leveling."

Facility energy managers can also take a full load shift approach by generating their cooling load overnight and storing it, then using that stored cooling in place of chillers to cool the facility for the entire day. By utilizing  a full load shift strategy, companies can see the greatest operational costs savings.

Three factors to consider
You'll have to consider several factors before deciding which energy storage strategy meets the needs of your facility. First, investigate your local utility's time of use rates,  demand charges and even incentives. Most areas of North America have half price electricity at night but buildings owners don't benefit from the savings because they don't really understand how they are charged for electricity. A surprising amount of savings can be found with just a little digging. Next, check the amount of space available. Be creative. Many clients find space in basements, storerooms, on roofs and in garages, etc. Ice storage, for example, is capable of storing more energy per pound than alternative storage mediums. As a result, ice is a far more space-effective medium for storage. Lastly, ascertain the availability of contractors that could provide support before and after the system is installed. If further assistance is needed, reach out to a thermal energy storage expert.