FOOD INDUSTRY SUSTAINABILITY Some complementary paths to a greener food industry
The global food industry is a high energy consumer; a situation it must address to reduce carbon footprint and save costs.This article looks at three possible ways to improve sustainability; buying green energy, building or investing in renewable energy sources, and upgrading onsite equipment and processes to improve efficiency.
It has been estimated that the food industry consumes 30 % of global energy and accounts for 20 % of greenhouse gas emissions. In Europe, it is estimated that food processing alone accounts for 28 % of the EU’s total energy use. The challenge of reversing climate change makes it increasingly important to reduce both the emissions from and energy used by the food and beverage industry. As a result, leading organizations like the European Commission, as well as the UN and the OECD, are trying to drive energy efficiency measures throughout the industry .
Food manufacturers of all sizes endeavoring to reduce their carbon footprint can go greener in three ways:
- They can ensure that they only buy energy from utilities who guarantee that their power comes entirely from renewable resources
- Larger organizations especially can develop their own energy generation from various types of renewable resource.
- All manufacturers can review their production equipment and processes to identify where efficiency can be improved.
Buying from renewable resources
Corporations can buy green energy certificates - Guarantees of Origin (GOs) in Europe or Renewable Energy Certificates (RECs) in the US – to match their consumption. However, this does not contribute to the buildout of renewables.
Alternatively, they can sign a corporate power purchase agreement (CPPA) which is a long-term supply contract of renewable power and certificates usually under a fixed price structure. A CPPA guarantees that the energy can be traced back to a specific wind or solar farm.
CPPAs also reduce risks associated with power price fluctuations. If a corporate had locked in power prices through a CPPA a year ago, it would be protected against the record high power prices in the wholesale market that many countries have seen in recent weeks .
Investing in and owning renewable energy assets
This can be off-site, for example by having an equity share in a new project, or by co-developing a greenfield project in a different location. It can also be on-site, for example through a private wire from a nearby wind farm or solar panels on a factory rooftop.
McDonald’s USA has made major investments in both wind and solar power. In 2020, they completed new virtual power purchase agreements (VPPAs) for two major wind farms and a large portfolio of solar projects across three US states.
The three new projects will be constructed across Illinois, Oklahoma, North Carolina, and Ohio, after the developers secured backing from McDonald’s and other businesses. McDonald’s’ share of the projects will reduce the business’ annual Scope 2 (power-related) emissions by more than 2.5 million metric tons.
When these are added to two earlier VPPAs, McDonald’s USA estimates that the resulting emissions reductions will take it halfway to its climate action target for restaurants and offices. It is striving to reduce absolute emissions from this part of the business by 36 % by 2030, against a 2015 baseline .
Biomass energy can be obtained by burning waste from crops or other vegetable or animal material. However, the process emits CO2, so it is widely seen as increasing rather than reducing a carbon footprint.
Breweries producing alcoholic drinks like beer and sake can capture the CO2 produced by fermentation, and use it for both for production and for carbonating drinks. This saves money on gas that would otherwise have to be purchased, while reducing carbon footprint.
Food producers can harvest biogas from decomposing food waste. The waste is fed into anaerobic digesters where bacteria break it down to produce methane and other components. The methane biogas can be used like natural gas to provide heat, generate electricity, and power cooling systems, among other applications .
Preventing this gas from escaping to atmosphere as the food decomposes is important, as it is worse for the environment than CO2.
Improving production energy efficiency
Real improvements can be made at the facility level; the site’s equipment and processes can be reviewed, updated, and improved to reduce actual energy consumption. Manufacturers can perform these reviews themselves, or ask external specialists like ABB to provide an Energy Appraisal as a service .
In the food and beverage industry the processes that consume the most energy vary by segment. In some, fans and pumps are responsible for most of the energy use. For example, in the agriculture segment they are found in feeding and ventilation applications for animals, while in the dairy sector they perform cooling and refrigeration. In other segments, milling and mechanical processing use the most energy. Examples include milling and centrifuges in sugar processing, and grain milling in the ingredients sector. And in confectionary, milling as well as conches, compressors and mixers use most of the energy.
Most of these processes rely on electric motor systems, including steam systems, pumps and compressors, and heating, cooling, and refrigeration systems. However, although electricity consumption in the industry is high, electric motor systems also offer opportunities to save energy, especially within fans, pumps, compressors, and conveyor belts. These do not run at full speed continuously; they traditionally use mechanical regulation methods like valves, brakes and throttles to control their speed. In this kind of system, the motor is doing more work than necessary, and energy is being lost through the mechanical speed control.
Variable speed drives (VSDs) offer a more efficient way of running applications at partial load because they can control the speed and torque of an electric motor directly. This eliminates the need for mechanical speed control and oversized motors. With direct control of a motor, it can be controlled to match the actual process demand, enabling applications to run with high efficiency at a range of different speeds. As a result, VSDs can significantly improve energy efficiency throughout whole production chains.
ABB offers VSDs and control software that, together with their application expertise, can be used to optimize various processes throughout the food and beverage industry, ensuring that motor-driven applications, such as compressors, pumps, extruders, conches and conveyors, do the right amount of work at the right time.
Yet energy saving opportunities can be found across an entire food and beverage facility, not just directly within the production processes. For example, lighting systems can be made significantly more energy-efficient by changing over to light emitting diode (LED) technology. LED systems have advanced rapidly in the last decade, and can be a game-changer for the food and beverage industry's quest to reduce energy consumption. LED lighting consumes less, requires less maintenance and is cooler and brighter. Additionally, it offers a higher ROI than traditional halogen or incandescent lighting. Such systems are becoming more attractive in cost while increasing in efficiency .
A culture of energy efficiency
Ultimately, improving energy efficiency in the food and beverage industry depends on more than making technical changes to the plant. Ingraining a culture of conservancy among employees and stakeholders is perhaps one of the most important steps any production company can take to reduce their overall carbon footprint and achieve aggressive energy-conservation goals. They can conduct training sessions to discuss best energy practices and educate operators about how to make better decisions. They can also educate all stakeholders about the importance of energy conservation and provide specific steps about how they can integrate these best practices into their daily routines.