MNRE Issues Guidelines for Solar Cold Storage with Thermal Energy Backup

The Ministry of New and Renewable Energy (MNRE) has unveiled comprehensive guidelines for solar-powered cold storage systems equipped with thermal energy storage (TES) backup, poised to redefine India's cold chain infrastructure.

These guidelines, titled 'Design Specifications, Performance Guidelines, and Testing Procedure for Solar Cold Storage with Thermal Energy Storage Backup,' are the culmination of extensive stakeholder consultations and aim to standardise the design, performance, and testing of these vital systems. The guidelines are effective immediately and will be enforced across all central and state government departments, agencies, and stakeholders involved in the implementation and operation of solar cold storage facilities nationwide.

The MNRE's new guidelines provide a detailed framework for solar cold storage systems, covering everything from the fundamental components to performance benchmarks and rigorous testing protocols. These systems, powered by solar photovoltaic (SPV) panels, offer a sustainable alternative to traditional cold storage methods, reducing reliance on fossil fuels and minimising environmental impact. The guidelines define a solar cold storage system as one that utilises SPV panels to generate electricity during daylight hours, powering a refrigeration unit while simultaneously charging the TES unit. This stored cooling energy, often in the form of phase change materials (PCMs), enables the system to maintain the desired temperature even in the absence of sunlight or during power outages.

The guidelines address a critical need for efficient and reliable cold storage solutions for perishable goods, including fruits, vegetables, dairy, fish, and pharmaceuticals. By specifying temperature ranges suitable for diverse products and mandating a precooling capacity of 10 percent of the total storage capacity for two consecutive days, the MNRE aims to ensure the effectiveness and reliability of these systems. The guidelines cover various capacities, from 2 MT to 20 MT, catering to a range of needs. The MNRE believes these guidelines will empower farmers and small-scale entrepreneurs by providing access to reliable and sustainable cold storage solutions, thereby minimising post-harvest losses and promoting economic growth.

The guidelines delve into the technical aspects of solar cold storage systems, specifying minimum design requirements for each component. These specifications encompass the cold room (insulation, materials, dimensions), the refrigeration unit (refrigerant type, compressor), the TES system (PCM lifespan, monitoring), the solar system (PV module specifications, mounting structures, earthing), and the battery system for auxiliary components. Furthermore, the guidelines emphasise the importance of remote monitoring systems to track crucial parameters such as temperature, humidity, and solar generation. To ensure long-term performance and reliability, the MNRE guidelines mandate a 5-year comprehensive maintenance period for all installed systems. The document also outlines detailed testing procedures to evaluate system performance, including cooling capacity, TES efficiency, and solar system output.

The testing procedure includes three key tests: evaluating the cooling delivery capacity of the TES and minimum achievable temperature, assessing solar performance and autonomy using an SPV array simulator, and testing the automatic power source switching operation. These tests involve precise temperature measurements, controlled heat load application, and detailed monitoring of energy consumption and system performance. The guidelines also include valuable annexures, such as NCCD references for appropriate temperature ranges for various commodities and a template for technical specifications.

With over 1,400 solar cold storage systems already installed across India, these standardised guidelines are expected to significantly accelerate adoption, contributing to food security, improved farmer incomes, and a reduced carbon footprint.

The MNRE's initiative marks a significant step towards a sustainable future for cold storage in India, promoting environmentally responsible practices and minimising post-harvest losses. Refer the document for further details.