Transition to Renewable Energy in the Dairy Cold Chain

The Problem

Milk production has grown considerably in India since the White Revolution of the 1970s. In fact, we are the world’s largest milk producer, responsible for around 23% of the global milk production. Most of this produce is consumed domestically, with marginal exports. This is not without its challenges. Since milk is a highly perishable commodity and the milk collection system in the supply chain is unorganised, its storage, distribution, and sale constitute a complex socioeconomic phenomenon.

While dairy is a crucial livelihood for many rural households in India, it is an unorganised sector dominated by small and marginal farmers. Even in the top milk-producing states, technological advancements have been minimal. This lack of technology often leads to high wastage and inconsistent quality and quantity of milk produce, affecting a crucial income-generation source for dairy farmers. Other challenges include high transportation cost, the time needed to deliver the milk to the nearest chiller, and the unavailability of local service providers of efficient milk chilling technologies.

Adopting technological solutions and reliable energy supply can make production efficient and reduce supply-chain waste. An improved cold chain with rapid chilling facilities will make this transformation possible. Erratic electricity supply leads to a loss of at least 3 per cent of the milk produced. Cooling the milk in a chilling centre takes up 25-30 per cent of the total energy consumption of a dairy farm. Typically, the milk received at dairies or milk collection facilities is at 35°C – 37°C. The milk must then be cooled to a safe storage temperature of 4°C to prevent microbial activity. Cooling tanks are used to increase the shelf life of milk as they arrest bacterial growth, retain freshness, and enhance milk quality. Diesel generators are traditionally used as backup sources of power due to frequent power outages in rural villages, making the cold chain infrastructure expensive to operate and raising its greenhouse gas emissions.

A Potential Solution

Through the ‘Energy Transition in Dairy Cold Chain’ project, WWF-India has provided a unique solution to village-based and farm-based collection centres by supporting them in installing milk chillers powered by a battery-supported solar PV unit. These chillers bring down the temperature of collected milk from around 35°C to 4°C-6°C instantly. This seizes microbial development in the milk and improves its shelf life significantly.

WWF-India has worked closely with dairy co-operatives and small private dairies to install solar-powered milk chillers. So far, 38 such chillers with a total capacity of 175 kW have been installed across Uttar Pradesh and Rajasthan. WWF-India aims to build up 1,000 kW of distributed solar-powered cold chain in the dairy sector.

The Impact

A transition to renewable energy and energy-efficient technology would reduce greenhouse gas emissions, energy consumption, and operational costs, and improve farmers’ income by INR 1.00/litre through improved milk quality. As per estimations, a milk chilling centre equipped with a 7 kW solar system to meet 100 per cent of its energy demand for running a 1,500-litre milk chiller unit can bring down CO2 emissions by 20.51 metric tons and energy consumption by 273,450 kWh in a year.