The problem with controlling power expenses for grower-shippers is that the power utility companies sometimes don’t know what they’ll be paying for electricity from day to day.

To cover these costs, utilities are forced to hike their rates exponentially at high usage periods during the month.

Bob Zak, president and general manager of Powerit Solutions North America, Seattle, thinks his company has the solution for grower-shippers to maximize energy efficiency during periods of rate spikes. It’s called Spara RTP — or real-time pricing — control. Zak said it helps large packing facilities wanting to conserve energy and cut down on electricity bills.

“(RTP gives you) automatic containment and control that helps get the most out of the power schedule,” Zak said. “There are a lot of creative things forced upon (utilities’) rate schedules. The amount companies can leverage these rate schedules and charges can go a long way toward cutting energy costs.”

Zak said one thing most people don’t understand is that it’s not easy for utility companies to raise rates.

“It’s very regulated,” he said. “They have to make a justification.”

Meanwhile, he said, the rates utilities pay for energy is changing constantly, largely because of facing greater government requirements for green power — such as wind or solar.

“If a utility is providing the bulk of its power at 3 p.m. and the wind dies, they have to go buy power somewhere else, and it costs more at the last minute,” Zak said.

To compensate, utilities often will tell customers it will charge a lower rate 90% of the time if the customer agrees to pay a premium cost the other 10%.

Zak said RTP detects when those premium-price times are and automatically adjusts a facility’s systems so that energy is conserved until the cheaper consumption periods return, when the energy can be ratcheted back up.

In a recent case study with Oxnard, Calif.-based Mission Produce, a Spara system was installed and Mission’s energy bill was reduced by as much as a third even while production increased and it was able to shed 500 kilowatts for demand response. The system adjusted refrigeration controls by implementing compressor staging and sequencing and accurately controlling temperature and defrost in cold rooms. The system automatically balances refrigeration needs with utility bill penalties.

“We use the rate schedules to our advantage,” Zak said.

Spara RTP accomplishes the same thing, only in real time.

In addition to Mission Produce, some of Powerit’s customers in fresh produce include Guadalupe Cooling Co. Inc., Guadalupe, Calif., Anchor Warehouse Services, Porterville, Calif., and Four Star Fruit, Delano, Calif. Anchor reported a 17% reduction in its monthly power usage during a case study with Powerit’s system.

Zak said there was a good reason why his company’s technology focuses on grower-shippers in fresh produce.

“We do a lot for food manufacturing, because it’s energy-intensive,” he said.

Zak also said companies typically can make back the cost of the solution through energy savings and government incentive programs that pay a portion to all of the costs for the program. For instance, in the Mission Produce case, the company qualified for a Southern California Energy rebate that paid for $177,750 of the system.