Energy is ubiquitous in modern society. The trick is shuttling it to places and applications where it can be exploited most effectively. Here are seven devices that could one day help conserve power and smooth out surges on the grid.
1. Frozen Foods. While flowers, vegetables and fresh meats can be harmed by freezer burn, it’s difficult to hurt frozen pork chops. It’s even more challenging to lay a scratch on the average rock-hard Spicy Jalapeno, Bean and Cheese Chimichanga from a convenience store freezer case. If Agatha Christie had lived in El Monte, California, she'd have had a character use a Hungry Man Pot Pie as a murder weapon.
EnerNoc, along with Bonneville Power, will conduct a trial to determine whether it can store power by exploiting cold storage facilities. Right now,solarand wind farms often produce power when it’s not wanted, i.e., at night or during times when an overabundance of power exists. Under the power shifting plan, the cold storage facility would take the power opportunistically, run their compressors more aggressively at the time, and plunge their meats into the sub-zero range. When the excess power ceased, or when a demand response event emerged, the compressors could be shut off. You could even give away the power because of the savings in peak power.
The frozen foods would subsequently rise back to their comfortable 32 degrees Fahrenheit level.
2. Old Books. Book storage facilities rely on cool air too, so the compressors can be gauged to float with the price and quantity of available power, said Sila Kiliccote, Commercial Sector Demand Response Lead at Lawrence Berkeley Lab during a recent field trip by GTM to the lab.
Air conditioning and refrigeration consume 13 percent and 4 percent, respectively, of the total energy consumed in commercial buildings and 13 percent and 7 percent of energy consumed in homes. Homes and commercial buildings account for 39 percent of all energy consumed in the U.S., according to the EIA and DEO. Ergo, compressor-powered devices account for 4 percent to 8 percent of all of our power.
3. Natural Disasters. Disaster recovery services, provided by companies such as Sungard, represent a multibillion-dollar industry built on waiting for the worst. When an earthquake halts your San Francisco datacenter, applications get rolled over to the backup center in Oklahoma.
Is it possible to start rolling applications to save money? People are looking into the idea, said Grilish Ghatikar, dynamic pricing and demand response standards and codes lead at Lawrence Berkeley.
Power Assure and other datacenter management startups have talked up the concept of rolling applications from place to place to conserve power. While it sounds dreamy and complex, it’s becoming more practical.
4. FM Radio. Home automation has yet to become widespread, in part, because of the cost of retrofitting thermostats and appliances for demand response services and automation. It can cost $300 to incorporate basic automation into a home. Commercial automation has gone farther, but most small businesses do not participate in demand response programs and most don’t have building management systems.
The Sacramento Municipal Utility District has been testing a Radio Data System (RDS) in 78 commercial establishments. In this trial, SMUD sends a signal, via FM radio, to thermostats in 78 commercial establishments that effectively turns down the air conditioner.
The RDS signals travel only one way. Users can’t provide feedback, but it’s cheap. SMUD only had to install one RDS server and ongoing service only costs $500 a month.
"It is very cheap to send a signal that goes to everyone," says Karen Herter of Herter Energy Services.
5. Ice Machines. Southern California Edison has been linking ice machines in fast food outlets to demand response networks. If 50 percent of the ice machines in SCE's service territory were put on aggressive demand response programs, the utility could obtain 90 megawatts' worth of peak power, according to Carlos Haiad.
Curbing power to 20 percent of the display cases in its service region would harvest 43 megawatts, while doing the same with 20 percent of the walk-in coolers would yield 35 megawatts.
"There are ranges of acceptable temperatures [for refrigerators], but within that range, there is a lot to play with," he said.
It is possible to be more aggressive with ice machines than freezers or fridges, because ice machines come with a built-in storage unit. If the ice tray fell below 25 percent capacity, the ice machine would make ice and override incoming demand response signals. If the ice tray was 30 percent to 50 percent full, the restaurant could not override the demand response signals.
Even more energy could be saved if fast-food outlets made all of their ice for use throughout the day the night before. But restaurants and convenience stores would have to make three times as much ice as they do now. "If you try to triple the size, they can't fit it in," he said. "Good ol' Taco Bell only has so much storage."
The concept is similar to the ice air conditioners from companies like Calmac and Ice Energy, but it allows small businesses to participate more easily with a lower perceived risk.
6. Gravity. Vycon makes equipment for cranes that captures the kinetic energy of falling cargo crates and converts it to electric power for industrial equipment. Gravity Power and Escovale want to exploit heavy rocks for power storage. Everything else on the list deals with power distribution, but gravity and movement, potentially, remain untapped sources for local power. EnOcean and others, at the other end of the spectrum, believe they can commercially harvest micro-vibrations to run light switches or motion sensors.
Bonus: Two Expected, but Underutilized, Sources of Negawatts
7. Datacenters. Similar, but different than number three. IT managers have begun to aggressively push the temperature/air conditioning settings in their data centers to cut down on air conditioning costs. NetApp saves $1.2 million a year on a retrofit that cost around $1.4 million -- in large part by keeping temperatures high.
Some datacenter managers are now looking at ways to synchronize their cooling strategies with power prices. One could pre-cool servers before 1:00 pm and then let the air conditioners float toward a high temperature mark before starting them up again. “You could raise the temperature for two hours a day,” said Ghatikar. Another technique: use fewer servers, but use them each to a greater capacity, during particular times of the day.
8. Lights. An easy one. PG&E has estimated that only one percent of California office lights are networked. Once networking -- from Digital Lumens, Redwood Systems, Lumenergi or someone else -- is in place, the lights can be linked to a demand response network. LED lights, which consume far less power than regular lights, would also reduce the need for air conditioning, giving facilities managers more flexibility to play with their AC units and refrigerators to save power.
Which brings us back to doe.