Summary

Ductless Mini-Split Heat Pump for Small Commercial Applications

Heat Pumps for Small Commercial Applications: Ductless Mini-splits vs. Conventional

Ductless mini-split heat pump employing variable refrigerant flow technology without simultaneous heating and cooling, and up to eight zones to be used for small commercial applications. Features of this technology include: 1. A single outdoor unit that provides non-simultaneous heating or cooling; 2. One to eight indoor units. 3. Each indoor unit can serve a separate zone, or can be combined with two or more units serving a single zone.

Synopsis:

Ductless mini-split heat pumps without simultaneous heating and cooling and with up to eight zones are a good match for small commercial applications. Notable features of this technology include:

1. Outdoor equipment that provides non-simultaneous heating or cooling.
2. One to eight indoor units per outdoor unit.
3. Each indoor unit can serve a separate zone, or can be combined with two or more units serving a single zone.
4. Up to 5-ton total capacity per system.
5. Variable speed compressor, linear expansion valve, and variable speed fans.
6. Not limited to wall-hung indoor style, open to cassette, ducted, etc.

To take advantage of IEER, occupancies would not include data rooms and other locations that are in cooling all year and do not operate at part load. This technology is most applicable in locations that experience the effects of weather and occupancy changes.

Energy Savings: 38%

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.

Simple Payback, New Construction (years): 2.8 What's this?

Simple Payback, Retrofit (years): 16.7 What's this?

Simple Payback is one tool used to estimate the cost-effectiveness of a proposed investment, such as the investment in an energy efficient technology. Simple payback indicates how many years it will take for the initial investment to "pay itself back." The basic formula for calculating a simple payback is:

Simple Payback = Incremental First Cost / Annual Savings

The Incremental Cost is determined by subtracting the Baseline First Cost from the Measure First Cost.

For New Construction, the Baseline First Cost is the cost to purchase the standard practice technology. The Measure First Cost is the cost of the alternative, more energy efficienct technology. Installation costs are not included, as it is assumed that installation costs are approximately the same for the Baseline and the Emerging Technology.

For Retrofit scenarios, the Baseline First Cost is $0, since the baseline scenario is to leave the existing equipment in place. The Emerging Technology First Cost is the Measure First Cost plus Installation Cost (the cost of the replacement technology, plus the labor cost to install it). Retrofit scenarios generally have a higher First Cost and longer Simple Paybacks than New Construction scenarios.

Simple Paybacks are called "simple" because they do not include details such as the time value of money or inflation, and often do not include operations and maintenance (O&M) costs or end-of-life disposal costs. However, they can still provide a powerful tool for a quick assessment of a proposed measure. These paybacks are rough estimates based upon best available data, and should be treated with caution. For major financial decisions, it is suggested that a full Lifecycle Cost Analysis be performed which includes the unique details of your situation.

The energy savings estimates are based upon an electric rate of $.09/kWh, and are calculated by comparing the range of estimated energy savings to the baseline energy use. For most technologies, this results in "Typical," "Fast" and "Slow" payback estimates, corresponding with the "Typical," "High" and "Low" estimates of energy savings, respectively.

Details

Ductless Mini-Split Heat Pump for Small Commercial Applications

Heat Pumps for Small Commercial Applications: Ductless Mini-splits vs. Conventional

Item ID: 276

Sector: Commercial

Energy System: HVAC--Heat Pumps

Synopsis:

Ductless mini-split heat pumps without simultaneous heating and cooling and with up to eight zones are a good match for small commercial applications. Notable features of this technology include:

Baseline Example:

Baseline Description: Electric Resistance Heating
Baseline Energy Use: 10.5 kWh per year per square foot

Comments:

The 2009 Commercial Building Stock Assessment gives the actual electrical building EUI's for various types of heating and cooling systems (Table D-EA5). Office buildings with electric heating and cooling have a total EUI of 20.1 kWh/sf-year. Office buildings with no electric heating or cooling use only 8.2 kWh/sf-year, indicating that the combined HVAC ventilation, heating, and cooling energy use is 11.9 kWh/sf-year. (For all commercial buildings, including retail, the corresponding numbers are 19.9 and 9.4 kWh/sf-year, respectively, for a heating and cooling load of 10.5 kWh/sf-year). Since this technology can be applied to many types of non-office buildings, a baseline energy use of 10.5 kWh/sf-year is assumed ( NEEA, 12/21/2009).

Manufacturer's Energy Savings Claims:

"Typical" Savings: 43%

Comments:

This technology has resulted in a new testing standard by AHRI to accommodate the unique features that allow it to operate more efficiently than baseline. AHRI Standard 1230 finds this equipment to be about 15% more efficient than a conventional heat pump.

Best Estimate of Energy Savings:

"Typical" Savings: 38%
Energy Savings Reliability: 6 - Approved Measure

Comments:

BPA funded a study of ductless heat pump retrofits in ten small commercial building with electrical resistance heating (Ben Larson, Ecotope, "Ductless Heat Pump Retrofits in Multifamily and Small Commercial Buildings", for the BPA's Energy Efficiency Emerging Technologies Program", December 7, 2012) (Larson, 2012). Their study found that in the small office and retail commercial buildings studied, the DHP system provided more than 90% of the space heating requirements. This is much higher heating offset than in single-family residences where DHP units provide only 45% to 80% of space heating requirements due to the existence of peripheral rooms that a centrally located DHP cannot heat. In the small commercial sector, nearly all of the space heating requirements could be met with a single DHP.

Metering at six sites revealed an average heating energy savings of 4,185 kWh/year per site (or about 4.0 kWh/sf-year). Cooling savings were not estimated as some of the small establishments did not initially have air conditioning so cooling loads represented a "takeback" as did energy use due to operating the DHP in a ventilation or air circulation mode. The energy use reduction is thus taken as 4.0 kWh/sf-year/10.5 kWh/sf-year = 38.1%. (Note: We don't know the annual electrical energy use per sf for electric resistance heated small commercial establishments. This percentage times the baseline energy use per square foot yields an annual savings equal to what is observed in field studies).

Note: This is a deemed measure under the October 1, 2014 BPA "Energy Efficiency Implementation Manual". The deemed amount is $250/ton.

Energy Use of Emerging Technology:

6.5 kWh per square foot 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.))

Comments:

Although AHRI has a performace rating that shows this technology is, on average, 30% better than the baseline (when the baseline is a conventional heat pump). 20% is more indicitive of actual savings given actual operating conditions of the equipment when contrasted with a heat pump with savings increasing to 38.1% of baseline heating system energy use when the commercial building population consists of a mix of electric resistance heat and heat pumps.

Technical Potential:
Units: square foot
Potential number of units replaced by this technology: 61,170,120
Comments:

The Cadmus Northwest Commercial Building Stock Assessment study indicates that small commercial buildings with floor space less than 5,000 sf make up about 10% of the regional commercial building floor space of 2,704 million sf (Figure 9, page 19). (2,704 x 0.1 = 270.4 million sf). This technology could potentially be retrofit onto any small commercial building but we can only take energy savings for the portion of the building population that uses electricity for space heating and cooling needs. Electricity is used for 27.1% of the regional heated floor area (Table C-GB13) while 83.6% of the regional floor area is heated (Table C-GB5). The total floor area impacted by this technology is thus estimated as 270,000,000 sf x 0.271 x 0.836 = 61,170,120 sf ( NEEA, 12/21/2009)

Regional Technical Potential:
0.24 TWh per year
28 aMW
What's this?

Regional Technical Potential of an Emerging Technology is calculated as follows:

Baseline Energy Use * Estimate of Energy Savings (either Typical savings OR the high range of savings) * Technical Potential (potential number of units replaced by the Emerging Technology)

First Cost:

Installed first cost per: square foot
Emerging Technology Unit Cost (Equipment Only): $6.00
Emerging Technology Installation Cost (Labor, Disposal, Etc.): $0.01
Baseline Technology Unit Cost (Equipment Only): $5.00

Comments:

A couple of years ago, the cost was about $2,400 per ton ($6.00/sf). The baseline is estimated at $2,000 per ton ($5.00/sf). Rule of thumb for the commercial sector is 1 cfm/sf, 400 cfm/ton.

Cost Effectiveness:

Simple payback, new construction (years): 2.8

Simple payback, retrofit (years): 16.7

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.

Comments:

This technology has lower maintenance requirements and increased comfort and reliability. The cost effectiveness of this technology also depends on weather/climate conditions at the site and operational differences between owners.

Detailed Description:

This is a ductless mini-split heat pump technology without simultaneous heating and cooling, and with up to eight zones to be used for small commercial applications. Features of this technology include:

1. Outdoor equipment that provides non-simultaneous heating or cooling .
2. One to eight indoor units per outdoor unit.
3. Each indoor unit can serve a separate zone, or can be combined with two or more units serving a single zone.
4. Up to 5-ton total capacity per system.
5. Variable speed compressor, linear expansion valve, and variable speed fans
6. Not limited to wall-hung indoor style, open to cassette, ducted, etc.

Product Information:
Mitsubishi, Mr. Slim Daikin, Ductless mini split

Standard Practice:

VVT or standard heat pump

Development Status:

This is a mature technology, dominating over 80% of the HVAC sector in Japan, China and Europe for the last 20+ years. Heat pump technology itself is well-established. This is essentially a “new” way of applying an existing technology.

Non-Energy Benefits:

Longer equipment life, lower maintenance, increased comfort, quiet

End User Drawbacks:

This technology is more expensive, going from about $2,500/ton to about $3,500/ton. However, prices are coming down as contractors get used to the new technology and get more comfortable with its reliability.

Operations and Maintenance Costs:

Baseline Cost: $5.00 per: square foot per year
Emerging Technology Cost: $3.00 per: square foot per year

Comments:

Both the baseline and the ET have similar maintenance costs. The biggest difference in maintenance cost on the baseline technology is the compressor. The baseline compressor life is about 5 to 6 years. The ET compressors last 15 to 20 years.

Effective Life:

Anticipated Lifespan of Emerging Technology: 20 years

Comments:

This technology has been around for over 20 years in Japan and Europe without excessive failure to warrant anything less than a 20 year life. This longer life can be attributed to the “soft start” on fans and the compressor.

Competing Technologies:

This technology uses less energy than split DX, packaged, VAV, PTAC, 4-pipe, WSHP , unit ventilators and other technologies, as documented in AHRI’s efficiency tables. This technology provides better control of the temperature—leading to better comfort—due to its ability to vary four parameters: compressor, both fans, and expansion valve. Further, the thermostat does not maintain the temperature within a 5-degree deadband but, rather, maintains a relatively constant temperature throughout the day.

Barriers:
This technology is about $1,000 per ton more expensive than the standard technology. However, prices are coming down as contractors get used to the new technology and more comfortable with its reliability.

Previous heat pump technologies were not as effective at extreme temperatures as the proposed technology. This technology can be selected to provide full heating and cooling even at extreme temperatures due to the part load/variable speed ability (versus on/off of previous technologies).

Reference and Citations:

David Baylon, 08/12/2013. Ductless Heat Pump Impact & Process Evaluation: Billing Analysis Report
Ecotope, Inc.

Dyer, 06/17/2006. Approaching 20 years in the UK
Modern Building Services

Dyer, 06/17/2013. Approaching 20 years of VRF in the UK
Modern Building Services , 1

AHRI, 1/1/2012. Variable Refrigerant Flow Multi-Split Air-Conditioners and Heat Pumps Certification Program
Air-Conditioning, Heating and Refrigeration Institute , 1

Amarnath & Trueblood, 09/30/2009. Energy Efficiency Demonstration for Ductless Heat Pumps
Electric Power Research Institute , 1

CADMUS, 12/21/2009. Northwest Commercial Building Stock Assessment (CBSA): Final Report
Prepared by the CADMUS Group for the Northwest Energy Efficiency Alliance

Ben Larson, 12/07/2012. Ductless Heat Pump Retrofits in Multifamily and Small Commercial Buildings
BPA Energy Efficiency Emergency Technologies Program

Rank & Scores

Ductless Mini-Split Heat Pump for Small Commercial Applications

There is no TAG available for this technology.

Market Potential

Ductless Mini-Split Heat Pump for Small Commercial Applications

Last Edited:

6/20/2011 11:49:40 AM by StaceyW

Market Segment:

This technology is applicable to many different market segments. For this specific technology, the applicable segment is for small commercial applications. It is particularly appropriate for homes that have been converted into businesses.

For more details, see the applicability factors in the accompanying spreadsheet. /Documents/ductless%20HP%20-%20small%20commercial%20276%206-20-11.xlsx

Regional Fit:

Mini-split heat pumps with variable refrigerant flow (VRF) are a very good fit for the Pacific Northwest. Our moderate climate makes heat pumps in general a very popular choice, great for retrofit and new construction. The technology can also benefit from the intense interest and success of ductless mini-split heat pumps for residential use. Many utilities in the region are already offering incentives on ductless heat pumps and, along with the Energy Trust of Oregon and BPA, have funded an active consortium promoting this technology, called the Northwest Ductless Heat Pump Project (http://www.nwductless.com/).

Zones:

Heating Zone 1, Heating Zone 2, Heating Zone 3, Cooling Zone 1, Cooling Zone 2, Cooling Zone 3

Performance Trajectory:

This technology has been used for over 20 years in the residential and commercial sectors in Japan, China, and Europe. In fact, it dominates the market there, capturing more than 80% of the market. It has become available in the U.S. within the last few years. To accommodate the U.S. market, the indoor unit options have expanded from a ductless wall-hung unit to many other styles, including ducted, floor mount, ceiling mount, and cassette.

Product Supply and Installation Risk:

There is no foreseeable product risk. Similar technology using CO2 as a refrigerant is currently being developed, which promises to be safer and more efficient than VRF technology. In fact, it is already being marketed in Asia but is currently too expensive to compete in the North American market. Once fully developed, this technology may be used by the same manufacturers and will likely displace current technologies with little or no disruption. This CO2-based technology may create opportunities for new manufacturers; whoever cost-effectively develops the CO2-based technology first may have an advantage in the marketplace. There is no foreseeable shortage of product supply.

Technical Dominance:

Once this becomes a standard offering from more manufacturers, there is every reason to believe that the equipment will only get better as time goes on.

Market Channels:

The market channels will be the HVAC dealers and distributors working with engineers, architects, and contractors.

Regulatory Issues:

There are already code requirements for programmable electronic thermostats. These will have to be considered when developing deemed requirements for incentives.

Other risks and barriers:

The greatest barrier to implementation is initial cost. With financial incentives, this technology could become more cost effective, which would encourage its adoption by the target customers.

Basis of Savings:

Perhaps the cleanest method for specifying what would be deemed approved for incentives would be to specify that qualifed units must exceed the applicable energy code requirements by a certain percentage.

Completed:

6/20/2011 11:16:11 AM by Stacey Waterman-Hoey