Per Henrik Pedersen, Seren Poulsen & Ivan Katic

Danish Technological Institute

P. O.Box 141

2630 Taastrup

Denmark

Introduction

A solar powered refrigerator (SolarChill) has been developed in an international project involving Greenpeace International, GTZ, UNICEF, UNEP, WHO, industrial partners and Danish Technological Institute. The refrigerator is able to operate directly on solar PV panels, without battery or additional electronics, and is therefore suitable for locations where little maintenance and reliable operation is mandatory. The main objective of the SolarChill Project is to help deliver vaccines and refrigeration to the rural poor. To achieve this objective, the SolarChill Project developed — and plans to make freely available a versatile refrigeration technology that is environmentally sound, technologically reliable, and affordable. SolarChill does not use any fluorocarbons in its cooling system or in the insulation.

For domestic and small business applications, another type of solar refrigerator is under development. This is an upright type, suitable for cool storage of food and beverages in areas where grid power is non-existent or unstable. The market potential for this type is thus present in industrialised countries as well as in countries under development.

The unique feature of SolarChill is that energy is stored in ice instead of in batteries. An ice compartment keeps the cabinet at desired temperatures during the night. SolarChill is made from mass produced standard components, which results in a favourable cost compared with other vaccine solar refrigerators.

The SolarChill has undergone intensive laboratory tests in Denmark, proving that it fulfils the objectives set for the project. In addition, a field test programme in three different developing countries is ongoing with the aim to gather practical experience from health clinics.

The paper describes the product development, possible SolarChill applications and experience with the two types of solar refrigerators, as well as results from the laboratory and field test.

Background

A developing project funded by the Danish Energy Agency and conducted by the Danish Technological Institute started in 1999 in co-operation with Danfoss Compressors, Vestfrost and other Danish companies. The aim was to develop a photovoltaic powered vaccine cooler without battery back-up. Instead energy storage of ice should keep the temperature stable during nights and periods without sunshine.

In parallel to that discussions were held at various times (starting in 1998-99) between UNEP, WHO, Greenpeace and GTZ with the objective to promote environmentally sound refrigerators. The idea to bring all these interested parties together arose at a refrigeration summit in Chicago in November 2000, which then led to a common meeting at GTZ headquarters in 2001. This resulted in an international project with the aim to develop, test, and use environmental sound, affordable and reliable photovoltaic powered vaccine cooler.

The Solar Chill project is a unique partnership among key international agencies, research

and industry bodies. The Project Partners and their main respective roles are:

□ Greenpeace International provides project coordination and fundraising;

□ GTZ Proklima provides technology advice and assessment and fund raising;

□ United Nations Children’s Fund provides need analysis and technology advice and assessment;

□ United Nations Environment Programme provides overall technology assessment and policy advice;

□ World Health Organization provides equipment specifications and technology advice and assessment

□ Program for Appropriate Technology in Health provides technology advice and conducts field test

□ Industry partners: Vestfrost, Vibocold, Danfoss, Gaia Solar provide hardware

□ Danish Technological Institute coordinates the technology development;