Making wine takes a lot of energy. How South Africa’s vintners can cut back

Wine production consumes large amounts of energy and generates a sizeable quantity of greenhouse gases. A looming carbon tax and greater consumer awareness about reduced energy use has led to a growing interest in the energy performance of South Africa’s wine industry.

The agriculture and industry sectors combined account for nearly 50% of the country’s energy consumption. It takes approximately 2,618 GJ of energy to process one tonne of grapes into the finished product. This equates to over 700,000 kWh of electricity to process a tonne of grapes. That’s the consumption of 60 middle class homes per year. In 2015 just more than 1.5 million tonnes of grapes were crushed to produce around 1 billion litres of wine.

South Africa is one of the top ten wine producing countries in the world. Of the 1 billion litres of wine produced annually, nearly half is exported. Around 95% of the wine is produced in the Western Cape province.

There is now widespread acceptance that energy use in the industry needs to be reduced. Typically, this can be achieved in two ways: behavioural change, and technical interventions.

Greater energy efficiency

A number of factors are driving the industry to look at greater energy efficiencies. These include:

The rising cost of energy. This is expected to remain well above inflation in the foreseeable future with significant implications for the sector’s profitability.
The risk of high carbon footprint products in a competitive export market. The industry is now subject to the GreenHouse Gas Accounting Protocol of the International Organisation of Vine and Wine.
Concerns about the impact of climate change on the local industry given the close correlation between vintage quality and annual weather conditions.

The challenge is that farmers often don’t have enough time to focus on energy efficiencies. They are also constrained by limited finances.

Farmers also tend to focus only on improving technical interventions. There’s usually only one person responsible for energy in the winery. This means that knowledge is not easily accessible to the rest of the team.

We identified the need to develop an appropriate guideline to implement an energy management system. This was based on best practice from wine producing regions such as California and Australia. We tailored these for the South African context.

The energy management system

The system builds on the energy management standard of the International Organisation for Standardisation. It’s been adapted for wineries. Using case studies from South African wineries, it identifies typical energy saving opportunities. But energy efficiency and cost cutting initiatives can be expensive. So a systematic approach is needed.

Winemakers or operations manager must have a written energy efficiency plan listing the ways in which energy consumption can be reduced. The plan should include an energy consumption reduction strategy, training of staff to improve energy consumption and monitoring programmes. A dedicated energy and carbon management system has worked well at the Backsberg Estate Cellars, which has won international awards for its efforts.

The plan would document how, when, and where energy use will be monitored. It would also track how these results can be used to improve energy efficiency. Energy consumption data should then be collected and monitored to enable analyses of the winery’s energy usage. Real time data will allow the winemaker or operations manager to identify peak demands and high energy usage processes that could be targeted for energy reduction.

Energy efficiency should also be made a high priority when purchasing new equipment. There are new technologies that can help drive down consumption.

At the same time, existing equipment should be optimised through regular servicing and repairs. In particular, refrigeration and cooling systems provide an opportunity for cost reduction and energy efficiency.

Space lighting is another example of low hanging fruit. Existing light bulbs can be replaced with more energy efficient ones.

Overall, there should be programmes in place for all the energy consuming equipment on any wine farm. Energy reduction and cost cutting won’t happen all at once. But a combination of interventions can result in breakthrough improvements. This has been demonstrated by several wineries in South Africa.

The guidelines aim to address the industry’s key concerns. These include reducing dependency on costly energy services, becoming carbon neutral in terms of product offering, and addressing climate change concerns.

THE CONVERSATION.COM | AUTHOR: Alan Brent - Professor of Engineering Management and Sustainable Systems, Stellenbosch University