Cold Chain Innovation Hub Research: Part 2

The following report — “Evaluating the Philippines’ Food Cold Chain, Energy Efficiency and Environmental Impact” — includes desk-based research conducted by the Cold Chain Innovation Hub on behalf of the “Global Partnership for Improving the Food Cold Chain in the Philippines” project.

The report has been divided into three parts and reproduced below.

Clean Food Cold Chain Alternatives

Several clean cold chain technologies exist today. Some examples are listed below.

Pre-Cooling & Near-Farm Cold Storage

Portable, solar-powered cold rooms:

The Ecofrost Solar Cold Storage by ecoZen

Source: “Ecofrost: Made In India Solar-Powered Cold Storage To Reduce Crop Spoilage”, SmartWorld, September 22, 2018, “India’s Third Agricultural Revolution, Doubling farmers’ incomes through clean cold chains,” 2017, University of Birmingham, Birmingham Energy Institute

These insulated containers have cooling compartments and a refrigeration system driven by a solar roof. The refrigeration system simultaneously cools the produce and recharges the unit’s built-in cold storage panels made of phase-change materials.

The units can pre-cool and store produce. It can also control humidity and operation can be monitored via smartphone.

Small-scale solar-powered absorption chillers:

Small-scale solar absorption chiller by Solar Polar

Solar absorption chiller
Solar Polar is a British company that has developed a small-scale solar-powered absorption chiller. Absorption chilling is a well established technology that turns heat directly into cooling – without any electrical stage – through the vapour absorption cycle.

Solar-powered mobile cooling demountable trucks:

Solar-Powered Indian Cold-Chain Eutectic Solution by Cartwright Group

Demountable body truck
The British truck body builder Cartwright Group is developing another solar powered mobile cooling concept. Known as SPICES – Solar Powered Indian Cold-chain Eutectic Solution – the device comprises a demountable truck body with a solar roof. During harvest the unit is detached from the truck and left at the field, where farmers can load their crops to be pre-cooled and then transported directly to market in the same vehicle without further handling…Temperature is maintained through the combination of solar power and eutectic cold storage, and needs no external power supply or infrastructure investment by farmers.

The truck body can be detached and left at the field where crops can be pre-cooled and then transported directly to market. It is solar-powered and uses eutectic cold storage and needs no external power supply.


Replacing F-gases with natural refrigerants:

Several refrigerated vehicles with transport refrigeration units that use natural refrigerants such as CO2 and propane are available and in use in the market today.

Transfrig R290 Transport Refrigeration System

Carrier Transicold CO2 refrigerated trailer unit

Carrier CO2 refrigerated truck
Source: “Carrier Transicold – Natural Refrigerant Trailer unit with Biocoop”, 2018, Carrier, Youtube

In addition, electric Transport Refrigeration Unit’s (TRU’s) compatible with electric vehicles are available.

Thermo King E-200 electric TRU

Foodstuffs NZ 100% electric refrigerated logistics truck

Liquid carbon dioxide is also being used for TRUs rather than diesel powered refrigeration systems.

Thermo King CryoTech TRU

Additionally, liquid air/nitrogen is being used as both the fuel to drive the vehicle engine as well as the coolant to replace the diesel powered refrigeration system completely.

Dearman liquid air/nitrogen piston engine+TRU

The Pack House

What is a pack house?

Harvested produce is often brought to a common facility for preparation and storage pending transport to market. In its various forms, this facility is referred to as a packing-shed, a pack-house or a packing-house.

An integrated pack house designed for multiple horticulture crops was recently built in Haryana, India. It includes variety of sorting, grading, packing and cold storage facilities. An example can be seen here.

Haryana’s first integrated pack house (with sorting, grading, packing and cold storage facilities)

Haryana’s first integrated pack house
Source: Screenshot from “Integrated Pack House For Multiple Horticulture Crops”, March 22, 2020, PVPC Group Youtube

A packing-house can be defined as a designated facility where fresh produce is pooled and prepared in order to meet the requirements of a target market.

Source: “Good practice in the design, management and operation of a fresh produce packing-house”, Food and Agriculture Organization of the United Nations, Regional Office for Asia and the Pacific, Bangkok, 2012

Model integrated pack house

The proposed design of a model energy efficient, sustainable and modern pack house facility in Haryana, India was included in a 2019 report titled “Promoting Clean and Energy Efficient Cold-Chain in India” by the Shakti Sustainable Energy Foundation. The refrigeration system uses ammonia. The blueprint is shown below:

Drawing of proposed infrastructure
Source: MPEnsystems, et al 2019. Promoting Clean and Energy Efficient Cold-Chain in India, MP Ensystems, Shakti Sustainable Energy Foundation and University of Birmingham (2019)

Cold Storage

Modern energy efficient and natural refrigerant-based alternatives to traditional large cold storage refrigeration systems include low-charge ammonia and transcritical CO2 based systems.

What is low-charge ammonia?

Modern low-charge ammonia systems are large industrial refrigeration systems where an attempt has been made to reduce the amount of ammonia used in the system while retaining its energy efficiency.

In recent years, three types of low-charge ammonia systems have emerged as systems being used for cold storage and other industrial and commercial refrigeration systems.

Low-charge Ammonia: Optimized SystemAn optimized low-charge ammonia refrigeration system works by using the traditional industrial ammonia refrigeration technology and further optimizing it with low-charge components, such as specifically designed evaporators, controls, heat exchangers, compressors and condensers.

A properly designed low-charge optimized system, uses less than 6,053 lbs (2,746 kg) of ammonia and requires therefore fewer vessels, fewer pipes, smaller pipe diameters and no pumps.
Low-charge Ammonia: Packaged SystemA packaged ammonia system eliminates the huge quantities of ammonia inventory, and piping, by moving to smaller self-contained systems that are usually placed on the roof/ground outside preventing any danger from leaks.

These self-contained systems have about 4.3 lbs/TR (0.55 kg/kW) ammonia charge and usually combine the compressor, evaporator valve system and control systems into one easily installed and movable packaged system.
Low-charge Ammonia: NH3/CO2 SystemAn ammonia/CO2 system can come in various formats (such as cascade, CO2/NH3 with pumped volatile brine and ammonia DX system using liquid CO2 overfeed) but the main idea is to isolate the ammonia charge, which is usually between 4 and 6 lbs/TR (0.5 – 0.83 kg/kW), to the machine room and use the CO2 as the secondary coolant that can be pumped into cold rooms in the facility.
Source: “World Guide to Low-Charge Ammonia” Part 1, shecco, 2019

Transcritical CO2

In addition to low-charge ammonia systems, systems that employ the use of CO2 only have also emerged as energy efficient and sustainable solutions for cold storage facilities.

Hannaford, a Scarborough, Maine-based division of Ahold Delhaize, is one of the first U.S. grocers to employ a transcritical CO2 system in a refrigerated warehouse. Hannaford’s CO2 warehouse also contains one of the world’s largest refrigerated spaces (250,000 ft2; 23,226 m2) to use a transcritical system. The warehouse supplies 85 of Hannaford’s approximately 190 stores in New York, New Hampshire, Vermont and Massachusetts.

Four transcritical racks are planned in what is a replacement of the warehouse’s original, almost 30-year-old R22 system. Three of the racks are medium-temperature, two-stage, intercooled systems, while the low-temperature rack (the first installed) is single stage, with ejector defrost. The installation was completed in February 2020.

Food Retail and Food Service

In commercial food retail and food service, transcritical CO2-based refrigeration systems as well as hydrocarbon-based refrigeration systems have emerged as sustainable and energy efficient solutions. Moreover, several hydrocarbon-based refrigeration systems have already been installed in the Philippines in the past few years.

In August, Royal Duty Free – a Philippines-based chain of duty-free supermarkets – will retrofit one of its stores to use only R290 plug-in units combined with a water-loop system, according to a local refrigeration contractor, Cold Front Technologies Asia, Inc. The store is located in Subic Bay — a special economic zone a few hours’ drive northwest of the Philippines’ capital city of Manila. It will be “the first store in the country to use 100% R290-based refrigeration,” according to Emilio Gonzalez La’O, Cold Front’s president.

Technology Assessment Methodology

In order to contribute to the development of a clean and energy efficient food cold chain in the Philippines, the following best-practice assessment, measurement and analysis methodologies have been identified.

The listing of different methodologies must be further investigated and adapted to the requirements and limitations of the Philippine cold chain industry.

The following is a technology assessment methodology taken from the 2019 report titled “Promoting Clean and Energy Efficient Cold-Chain in India” produced by the Shakti Sustainable Energy Foundation.

It outlines the 8 major factors considered when selecting the most appropriate piece of technology to use in any given clean and energy efficient cold chain application.

Cost-Landed Cost (Percentage greater than Ammonia based VCC)
-Operation & Maintenance Cost (% cost of refrigerant system)
Specific Energy Consumption-Specific Energy Consumption (kWh/TR)
-GHG emissions related to operation (kg CO2)
Scale-Up Opportunity-Whether intensive training is required for operation and maintenance services
-Qualification of personnel to operate and maintain
-Scale-up opportunity (% of capacity)
-Development status of the technology
-Technology in existence for (years)
Local Capacity to Build-Energy requirement (units/day)
-Water requirement (litres/year)
-Water quality (source)
-Number of employees in the company
-Number of technology providers within district
Efficiency Gains-Efficiency gains (%)
Operation and Maintenance-Availability of after-sales services (in km radius from site)
-Availability of spare parts (% years of life of technology)
Compatibility with Closed Loop System-Compatible with renewable or waste heat recovery technologies
Global Warming Potential/Ozone Depleting Potential (GWP/ODP)-GWP related to refrigerant
-ODP related to refrigerant
Source: MPEnsystems, et al 2019. Promoting Clean and Energy Efficient Cold-Chain in India, MP Ensystems, Shakti Sustainable Energy Foundation and University of Birmingham (2019)

Continue to Part 3: Measuring Energy Efficiency and Environmental Impact