Trane has teamed up with Natgun, Ice Energy, and Calmac to help PG&E customers reduce peak demands for power while saving money. The $10 million Shift & Save Program taps into advanced technologies to achieve reliability, affordability, and an environmentally-sound energy future for PG&E customers. The various technologies that will deliver this benefit are:

Ice Storage Air Conditioning (ISAC) by Ice Energy

The Ice Bear® 30 Hybrid Air Conditioner provides efficient cooling using only a fraction of the energy required by conventional systems, dramatically lowering electricity costs and reducing greenhouse gas emissions. Air conditioning energy demand - typically 40-50% of a building's electricity use during expensive peak hours - is reduced by 95%.

The Ice Bear hybrid air conditioning system stores cooling energy by freezing water in an insulated storage tank. It cools by circulating chilled refrigerant from the tank during the day to the evaporative coil of the conventional A/C system, eliminating the need to run the energy-intensive compressor. Ice is then refrozen each night when demand is lower and electricity is cleaner, more efficient and less expensive.

This is ideal for applications with light commercial packaged equipment (Ice Bear).

Internal Melt Ice-Over-Coil (IMIOC) by Calmac Corporation

According to the Brattle Group, "Excess electric capacity has shrunk to a level barely within the planning toleration of the industry." This grid reliability issue, along with sustainable design and the goal to be more energy independent, has driven changes in California's Title 24 that encourage load shifting technologies. It has also reignited the thermal energy storage industry. In order to take advantage of cleaner, cheaper, off-peak and renewable energy, building owners, architects and engineers are turning away from the "just in time production" of conventional comfort cooling systems and moving toward hybrid cooling systems that use Ice-Based energy storage. California recognizes the value and cost of peak time energy and has added a "Time Dependent Valuation" (or TDV) component to Title 24, the state building code. When modeling a building using the "performance compliance approach" the TDV multipiers encourage and reward designers who shift energy to off-peak time periods. Thus, buildings with thermal storage will exceed the Title 24 code by larger margins.

CALMAC has been providing IceBank^® Ice-Based energy storage technology since 1953. Ice- based cooling not only provides the same comfort and reliability that you expect from any Trane cooling system, it also offers an added safety factor, reduced cooling costs and a lesser impact on the environment.

Using a standard Trane chiller to produce ice during the night, IceBank systems store that ice in modular energy storage tanks and use it to meet the building's air-conditioning requirements on the following day.

IceBank Ice-Based Cooling advantages include:

• Reduced carbon footprint and SOx and NOx emissions
• Less source energy consumption
• Helps make renewable energy strategies more viable
• Reduces peak kW demand
• Helps earn LEED® points
• Help to meet and exceed Title 24 Building Codes
• Lower cooling costs
• Reduces need to build additional power plants

IceBank Ice Storage: A Better Way to Air-Condition

Ice-based cooling is a proven method of shifting the cooling load from daytime to nighttime. And, because nighttime produced energy is plentiful, cleaner and often obtainable at a lower cost, it can play a vital role in relieving the state's energy quandary.

Stratified Chilled Water Storage (SCHWS) by Natgun

Thermal Energy (chilled water) is produced during periods of off-peak electrical demand (usually at night), collected in a thermal energy storage tank, and withdrawn and distributed through the facility during high demand peak rate hours. Warm and chilled water enters and exits the tank through diffusers located at the top and bottom of the tank. These diffusers are designed to eliminate turbulence and provide a stable, sharply defined transition layer, or "thermocline", thus allowing for the natural stratification of warm water at the top of the tank and chilled water at the bottom.

Five Ways a Natgun Thermal Energy System Lowers High Energy Costs

1. Reduce Demand Surcharges - Many commercial and industrial utility rates include a "demand charge" - a monthly surcharge based on the maximum kilowatts used by the individual customer during any peak rate period each month. A thermal energy storage tank allows customers to operate their chiller plant during the local utility's off-peak rate period, dramatically lowering the utility's peak rate demand surcharge.
2. Lower usage rates - Many utilities have established "time of use" rates as a way of encouraging customers to use less energy during daylight hours. Operating chillers during the evening, when off-peak rates are in effect, lowers the cost of electricity used for cooling.
3. Reduce Power Consumption - With thermal energy storage, chiller operation is shifted to evening hours, when ambient temperatures are cooler. As a result, chillers operating more efficiently and consume less energy for a given cooling load.
4. Defer Capital Equipment Purchases - In both new construction and facility expansion projects, a thermal energy storage system is often a cost-effective alternative to purchasing expensive chiller plant equipment. By utilizing a Natgun TES tank, capital expenditure outlays can be deferred and future operating costs dramatically reduced for years to come.
5. Lower Construction Costs - Some utilities offer substantial cash incentives and rebates to customers installing thermal energy storage systems.

TES tanks are ideal for applications with large chilled water cooling systems.