Commercial Heat Pump Water Heaters

Summary

Commercial Heat Pump Water Heaters

Commercial Water Heaters: Heat Pump vs. Conventional Electric

Remove heat from the immediate or outside atmosphere and transfer it to the water tank.

Synopsis:

Heat pump water heaters (HPWH) use heat pump technology to extract heat from air and transfer it to water. They are two to three times more efficient than conventional electric water heaters, and these efficiencies can be higher with advanced technologies.

HPWHs have been available for 20+ years but have not yet been widely adopted because of a general misunderstanding and misapplication of the technology, and the additional labor required to correctly install the units and supporting equipment. This is expected to change as promising new products enter the market. Technological improvements that increase the efficiency include:

Advanced variable speed compressors,
Removing the heat pump function from conditioned space, and
Carbon dioxide refrigerants.

While primarily targeting residential markets, this technology can also be used in commercial applications that generate substantial waste heat and have a high hot water demand. In addition, operations with a high cooling demand could benefit from HPWHs because they capture ambient heat. Examples of these applications include commercial kitchens, laundry facilities, waste water treatment facilities and hospitals. Some applications may require additional ductwork, dampers and controls to vent cool air when unwanted.

Energy Savings: 50%

Energy Savings Rating: Approved Measure What's this?

Level	Status	Description
1	Concept not validated	Claims of energy savings may not be credible due to lack of documentation or validation by unbiased experts.
2	Concept validated:	An unbiased expert has validated efficiency concepts through technical review and calculations based on engineering principles.
3	Limited assessment	An unbiased expert has measured technology characteristics and factors of energy use through one or more tests in typical applications with a clear baseline.
4	Extensive assessment	Additional testing in relevant applications and environments has increased knowledge of performance across a broad range of products, applications, and system conditions.
5	Comprehensive analysis	Results of lab and field tests have been used to develop methods for reliable prediction of performance across the range of intended applications.
6	Approved measure	Protocols for technology application are established and approved.

Details

Commercial Heat Pump Water Heaters

Commercial Water Heaters: Heat Pump vs. Conventional Electric

Remove heat from the immediate or outside atmosphere and transfer it to the water tank.

Item ID: 40

Sector: Commercial

Energy System: Water Heating--Water Heaters

Technical Advisory Group: 2010 HVAC TAG (#3)
Average TAG Rating: 2.9 out of 5
TAG Ranking Date: 06/29/2010
TAG Rating Commentary:

Most water heaters where this would apply are gas.
"The Power Plan has significant HPWH potential. Therefore, we will need to evaluate performance, appropriate applications, and customer acceptance. This project describes a relatively narrow niche. I am concerned about the ability to heat water hot enough to meet the needs of kitchens and laundries. Perhaps a resistance booster heater will be needed. I recommend a well-planned approach to testing HPWHs in the commercial sector."
Heat pump hot water heaters should be just around the corner, and I think we should encourage them at the same time we continue to reduce the amount of hot water needed. We may want to treat them as a general topic, not linked to AC. However kitchens and laundries are common...in large hotels, nursing homes, hospitals... There have in the past been products that simultaneously produced both services by moving the heat out of the air into the water. The challenge was in training installers and designers to set up the systems properly, particularly to handle times when the primary heat source or sink was not available. The question is whether the products and the know how could be made readily available in the next couple years. Would be interesting to pilot. Probably makes more sense to generally look at heat pump water heaters and identify where, for each type of occupancy, the heat should be found...exhaust air, etc. Focusing solely on kitchens and laundries as the first step might make the task overly difficult.
I support this for commercial kitchens, which almost always need cooling. This application may not need ducting & dampers. Not sure of there are heat pump water heaters on the market that are designed to have ducted condenser air. In applications that don't need cooling 24-7 the cost of dampers, controls, and perhaps a booster fan would compromise cost-effectiveness.
I see the biggest benefit of this technology on the DHW side. I see little residential or commercial benefit in space cooling as customers do not want the equipment in the conditioned/active space, and provision for ductwork and fans to move the air seems like more trouble than it is worth and will degrade the COP of the heat pump.
I think this technology has limited benefit for the Northwest region. Because we are so overwhelmingly heating-driven, there is little opportunity for simultaneous air conditioning and water heating demand. Unless the condenser is actually outside, the heat pump will end up using electric resistance backup once it has extracted the useful heat out of the garage. If the water heater is indoors, the heat pump will simply rob heat from the conditioned space that must be offset with more heat from the home's heating system. These systems are most beneficial in very warm southern climates.

Synopsis:

Advanced variable speed compressors,
Removing the heat pump function from conditioned space, and
Carbon dioxide refrigerants.

Baseline Example:

Baseline Description: Electric resistance water heater
Baseline Energy Use: 1200 kWh per year per unit

Comments:

Places that would install electric water heaters (because we can not count gas water heaters as baseline) are assumed to be relatively small hot water users. This is based on water use of 200 gal per day, 300 days/yr, and raising the water temperature from 50°F to 120°F.

Manufacturer's Energy Savings Claims: Currently no data available.

Best Estimate of Energy Savings:

"Typical" Savings: 50%
Energy Savings Reliability: 6 - Approved Measure

Comments:

This is based on the assumption that the alternative water heater is electric resistance, since BPA does not include measures to displace natural-gas-burning equipment. Heat pump water heaters tend to have an Energy Factor (EF) of about 2.0 vs. an electric resistance water heater, which would be almost 1.0 (0.96 or higher).

Note: This is a deemed measure under the October 1, 2014 BPA "Energy Efficiency Implementation Manual". The deemed amount is $300 to $500 per unit.

Energy Use of Emerging Technology:

600 kWh per unit per year What's this?

Energy Use of an Emerging Technology is based upon the following algorithm.

Baseline Energy Use - (Baseline Energy Use * Best Estimate of Energy Savings (either Typical savings OR the high range of savings.))

Technical Potential:
Units: unit
Currently no data available.

First Cost: Currently no data available.

Cost Effectiveness:

Simple payback, new construction (years): N/A

Simple payback, retrofit (years): N/A

What's this?

Cost Effectiveness is calculated using baseline energy use, best estimate of typical energy savings, and first cost. It does not account for factors such as impacts on O&M costs (which could be significant if product life is greatly extended) or savings of non-electric fuels such as natural gas. Actual overall cost effectiveness could be significantly different based on these other factors.

Reference and Citations:

BPA, 10/01/13. Heat Pump Water Heaters
Bonneville Power Administration

NEEA, 01/01/2012. Northern Climate Heat Pump Water Heater Specification
Northwest Energy Efficiency Alliance

BPA, 07/26/2010. BPA makes strides with utility partners on heat pump water heater demonstration
Bonneville Power Administration

Carl Hiller, 07/29/2010. Heat Pump Water Heater Technology
Building America Residential Buildings Energy Efficiency Meeting

Kate Hudon, 10/01/2013. Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models
National Renewable Energy Laboratory

Navigant, 09/30/2011. Research and Development Roadmap for Water Heating Technologies
Oak Ridge National Laboratory

Van Baxter, 09/08/2011. Analysis of highly-efficient electric residential Heat Pump Water Heaters for Cold Climates
Oak Ridge National Laboratory

B. Sparn, 10/01/2013. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters
National Renewable Energy Laboratory

FEMP, 09/17/1999. Commercial Heat Pump Water Heaters
Federal Energy Management Program

Energy Star, 2013. High Efficiency Electric Storage Water Heaters for Consumers
Energy Star

ORNL, 2013. The ‘Drop-In’ Residential Heat Pump Water Heater: A market-driven solution to energy efficiency
Oak Ridge National Laboratory

EERE, 08/29/2013. Heat Pump Water Heater Basics
Energy Efficiency & Renewable Energy

Rank & Scores

Commercial Heat Pump Water Heaters

2010 HVAC TAG (#3)

Technical Advisory Group: 2010 HVAC TAG (#3)
TAG Ranking: 13 out of 36
Average TAG Rating: 2.9 out of 5
TAG Ranking Date: 06/29/2010
TAG Rating Commentary:

Most water heaters where this would apply are gas.
"The Power Plan has significant HPWH potential. Therefore, we will need to evaluate performance, appropriate applications, and customer acceptance. This project describes a relatively narrow niche. I am concerned about the ability to heat water hot enough to meet the needs of kitchens and laundries. Perhaps a resistance booster heater will be needed. I recommend a well-planned approach to testing HPWHs in the commercial sector."
Heat pump hot water heaters should be just around the corner, and I think we should encourage them at the same time we continue to reduce the amount of hot water needed. We may want to treat them as a general topic, not linked to AC. However kitchens and laundries are common...in large hotels, nursing homes, hospitals... There have in the past been products that simultaneously produced both services by moving the heat out of the air into the water. The challenge was in training installers and designers to set up the systems properly, particularly to handle times when the primary heat source or sink was not available. The question is whether the products and the know how could be made readily available in the next couple years. Would be interesting to pilot. Probably makes more sense to generally look at heat pump water heaters and identify where, for each type of occupancy, the heat should be found...exhaust air, etc. Focusing solely on kitchens and laundries as the first step might make the task overly difficult.
I support this for commercial kitchens, which almost always need cooling. This application may not need ducting & dampers. Not sure of there are heat pump water heaters on the market that are designed to have ducted condenser air. In applications that don't need cooling 24-7 the cost of dampers, controls, and perhaps a booster fan would compromise cost-effectiveness.
I see the biggest benefit of this technology on the DHW side. I see little residential or commercial benefit in space cooling as customers do not want the equipment in the conditioned/active space, and provision for ductwork and fans to move the air seems like more trouble than it is worth and will degrade the COP of the heat pump.
I think this technology has limited benefit for the Northwest region. Because we are so overwhelmingly heating-driven, there is little opportunity for simultaneous air conditioning and water heating demand. Unless the condenser is actually outside, the heat pump will end up using electric resistance backup once it has extracted the useful heat out of the garage. If the water heater is indoors, the heat pump will simply rob heat from the conditioned space that must be offset with more heat from the home's heating system. These systems are most beneficial in very warm southern climates.