05. Energy efficient cold storage – Above Green

(3 credits available)

Aim

To recognise and encourage the installation of energy efficient refrigeration systems, therefore reducing operational greenhouse gas emissions resulting from the system's energy use.

Assessment criteria

The following is required to demonstrate compliance:

One credit - Energy efficient design, installation and commissioning

With respect to the refrigeration system, its controls and components:

1.a

A strategy for the design and installation has been produced and implemented by a Suitably qualified engineer from Concept Design stage onwards. The strategy is multidisciplinary and contains both an aim and a method to achieve the lowest practicable environmental impact including energy use, carbon emissions and refrigerant impact

1.b

The design team has demonstrated that the cold store and the building has been designed to minimise heat loads through high levels of insulation, reduced air infiltration and minimisation of auxiliary heat loads, e.g. fans and pumps, lighting, people and machinery

1.c

At least 50% of the relevant energy efficient design features (refer to CN2.1) have been specified or installed

1.d

Control systems have been installed to minimise refrigerant temperature lifts by providing controls that optimise evaporator temperature levels and avoid head pressure control

1.e

Energy sub-metering has been installed to provide adequate central monitoring of operating parameters and collection of data on plant performance, temperature levels and energy consumption. This does not necessarily require the 'energy monitoring' credits to have been awarded

1.f

The design has minimised the requirement for manual override of plant controls and equipment in normal operating conditions through the specification of central automatic controls, anti-tamper controls, automatic lighting controls, fixed set-point temperature and temperature dead bands

1.g

The design specification details appropriate commissioning and test procedures to be undertaken at completion

1.h

The installation adheres to the design specification and any necessary changes have been carried out with the approval of the Suitably qualified engineer and are formally documented.

The refrigeration system has been commissioned as follows:

2.a

In compliance with criterion 5 for 'Commissioning' outlined in BREEAM issue Man 04 Commissioning and handover. This does not necessarily require the 'Commissioning' credits to have been awarded

2.b

Documentation has been provided showing due diligence and compliance with test and commissioning procedures relevant to the installation, such as pressure testing, leakage testing and validation to specification.

One credit - Energy efficiency criteria

The refrigeration system uses robust and tested components that meet published energy efficiency criteria (refer to CN2.2).

One credit - Indirect greenhouse gas emissions

Criteria 1 and 2 are achieved.

The installed refrigeration system demonstrates a saving in indirect operational greenhouse gas emissions (kgCO2e) with respect to a 'baseline' building through specification of available technologies. The indirect emissions have been calculated using the Total Equivalent Warming Impact (TEWI) equation as defined in the calculation procedures section.

Checklists and tables

None.

Compliance notes

Ref	Terms	Description
Applicable assessment criteria
CN1	Part 1: Fabric and structure	This issue is not applicable
CN1.1	Part 2: Core services	Criteria 1 to 5 are applicable
CN1.2	Part 3: Local services	Criteria 1 to 5 are applicable
CN1.3	Part 4: Interior design	Criteria 1 to 5 are applicable
General
CN2	Scope of this BREEAM issue	This issue is applicable only in instances where commercial or industrial-sized refrigeration and storage systems are specified, for example: Storage and refrigeration of food in supermarkets Cold storage facilities in industrial, laboratory, healthcare and other buildings. The criteria do not apply to: Residential-scale refrigeration Refrigeration for kitchen and catering facilities. These types of installation are covered within BREEAM issue Ene 08 Energy efficient equipment. If the building does not contain commercial or industrial-sized refrigeration systems, this issue is not applicable to the assessment.
CN2.1	Energy efficient design features	Below are some design options that are intended to achieve best practice energy efficiency of the cold storage equipment. Fit energy efficient lighting with suitable controls and high efficiency fans on evaporators. Minimise loss of cold air through access doors by minimising frequency of door opening or by fitting air curtains, self-closing doors, door strips, etc. Optimise evaporator temperature levels to keep suction or evaporation temperatures as high as possible. Specify high efficiency compressors. Provide controls on anti-sweat heaters on doors to minimise electrical consumption outside of operational hours. Condensing temperatures that are as low as possible, including avoiding head pressure control. Design evaporators and condensers for easy cleaning and safe access. Optimise defrosting methods to minimise energy consumption and avoid electric heater defrost. High evaporating temperature cabinets (large coils) with single evaporating temperatures across the refrigeration pack for supermarket display cases. Provision of heat recovery in the design such as de-superheating to domestic hot water, condensing to hot water for heating. (If specified this must not lead to condensing conditions that are artificially inflated to deliver the heat recovery.) Use of wet condensing-based systems. Use of re-manufactured items that are still of an energy efficient nature where they do not compromise the optimal energy efficiency of the cold storage equipment. Not all of these energy efficient design features will be relevant to the cold storage being assessed. Where features are to be excluded the suitably qualified engineer must provide written justification for determining which are unachievable.
CN2.2	Published energy efficiency criteria. See criterion 3 .	Please refer to the country-specific reference sheet to locate the appropriate published energy efficiency criteria in the country of assessment. Alternatively, please demonstrate that the eligibility criteria are equal to or more onerous than those in the ECA Energy Technology Product List (ETPL): etl.decc.gov.uk. Where specified as part of the refrigeration system, products used for the following components must meet published energy efficiency criteria: Air-cooled condensing units Automatic air purgers Cellar cooling equipment Commercial service cabinets (cold food storage) Curtains, blinds, sliding doors and covers for refrigerated display cabinets Evaporative condensers Forced air pre-coolers Refrigerated display cabinets Refrigeration compressors Refrigeration system controls.
CN3	Refurbishing part of an existing building	Where only part of an existing building is being refurbished and there is cold storage that will serve both the refurbished part and the unchanged part of the building, then this plant must meet the criteria in order to achieve any available credits.

Methodology

Calculating indirect greenhouse gas emissions (CO₂ₑ.) using TEWI

When calculating the Total Equivalent Warming Impact (TEWI) factor, the following equation must be used where the various areas of impact are correspondingly separated:

Total Equivalent Warming Impact (TEWI) equation

As the criteria looks only to calculate the indirect emissions from the refrigeration system, only the impact of the energy consumption of the system needs to be calculated:

TEWI (Indirect Emissions only) equation

TEWI Equation Terms
	Total equivalent warming impact (kgCO2e)
	Impact of leakage losses
	Impact of recovery losses
	Impact of energy consumption
	Global warming potential of gas in the insulation (CO₂ related)
	Global warming potential (CO₂ related)
	Leakage (kg/yr)
	System operating time (yr)
	Refrigerant charge (kg)
	Recovery or recycling factor between 0 and 1
	Energy consumption (kWh/yr)
	CO₂ emission (kg/kWh)
	Refrigerant charge in the insulation system (kg)
	Rate of gas recovered from the insulation at the end of life between 0 and 1
The GWP is an index describing the radioactive characteristics of well-mixed greenhouse gases that represent the combined effects of the differing times these gases remain in the atmosphere and their relative effectiveness in adsorbing outgoing infrared radiation. This index approximates the time integrated warming effect of a given greenhouse gas in today's atmosphere, relative to CO₂. The conversion factor β gives the quantity of CO₂ produced by the generation of 1 kWh. It can vary considerably geographically and in terms of time.

Calculations must be carried out by a Suitably qualified engineer (e.g. a building services engineer), including calculations to justify the assumptions and methodologies for savings in indirect greenhouse emissions.

Evidence

criteria	Interim design stage	Final post-construction stage
All	One or more of the appropriate evidence types listed in 4.0 The BREEAM evidential requirements section can be used to demonstrate compliance with these criteria.
2	Refer to the generic evidence requirement above..	Refrigeration plant commissioning record

Additional information

Relevant definitions

ECA Energy Technology Product List (ETPL)

The ETPL is part of the government's Enhanced Capital Allowance Scheme, a key part of the government's programme to manage climate change. The scheme provides a tax incentive to encourage investment in low carbon energy saving equipment that meets published energy efficiency criteria. The Energy Technology List (ETL) details the criteria for each type of technology, and lists those products in each category that meet them:etl.decc.gov.uk/etl/site.html.

Indirect operational greenhouse gas emissions

These are the indirect greenhouse gas emissions that result from the production of energy used to power the refrigeration system's cooling plant. This includes the emissions from the production of grid electricity or an on site source of energy generation, e.g. gas CHP. In the case of refrigeration systems, the term 'direct greenhouse gas emissions' is also used; this refers to the emissions that occur as a direct result of leakage of refrigerant from the system. The impacts of direct greenhouse gas emissions from refrigeration systems are dealt with in the BREEAM issue Pol 01 Impact of refrigerants. Therefore, only indirect emissions resulting from the energy consumption of the system are covered in this issue.

Suitably qualified engineer

An individual achieving all the following items can be considered to be 'suitably qualified' for the purposes of this BREEAM issue:

Has the authority to make decisions in regards to the final design
Holds a degree or equivalent qualification in building services engineering or a relevant related subject
Has a minimum of five years relevant design experience (Suitably qualified engineer within the last seven years). Such experience must clearly demonstrate a practical understanding of factors affecting the design of cold storage and include related CPD.

Other information

Code of Conduct for carbon reduction in the retail refrigeration sector

The Code of Conduct has been developed by the Carbon Trust, in partnership with the Institute of Refrigeration (IoR) and the British Refrigeration Association (BRA). The Code is intended to compliment the Carbon Trust Refrigeration Road Map.