By Eamonn Ryan
In recent years, there has been a growing interest in sustainable and energy-efficient solutions to reduce the carbon footprint of the transportation industry.
One such solution is the use of solar-powered refrigeration systems in place of traditional diesel-powered systems. NextDrive, a leading provider of refrigerated transport solutions, has been at the forefront of this green revolution in South Africa.
By fitting refrigerated trucks with solar panels, the company has been able to significantly reduce carbon emissions while ensuring the safe and efficient transportation of perishable goods.
Warren Hurter, co-founder and technical director of solar refrigeration transport business NextDrive, discusses the efficiency of solar-powered refrigeration in contrast to traditional systems powered by diesel motors. “Such systems boast efficiencies exceeding 90%, compared to traditional engines maxing out at around 25%, in addition, the reduction in moving parts contributes to lower maintenance requirements.”
Hurter says: “Our primary focus is the transport sector: my background traces back to the University of Johannesburg where I was involved in the development of solar-powered racing cars – a venture that laid the foundation for our journey. Fast forward to the present; we started as consultants for ShopRite Checkers, assisting them in exploring the feasibility of running their trailers’ refrigeration units on trucks using a solar system instead of conventional fuel. After conceptualising the idea, we not only proposed it but also took the initiative to implement it for them. That marked the inception of our business.
“Six years down the line, we manage 1 600 of their trailers, offering comprehensive services covering refrigeration, security and more. In essence, our focus revolves around three core areas: solar logistics, solar refrigeration, and commercial solar. These areas define our expertise and commitment as we strive to contribute to a sustainable and eco-friendly future.”
He highlights the significance of batteries and inverters. “While the system design is relatively simple – mirroring a residential setup – the challenge with a transportation system lies in intelligently packaging it in a vehicle with its inherent exposure to rough conditions on roads, as well as to enable remote monitoring, and address safety considerations during accidents. The company imports key hardware components, rigorously testing and proofing them through multiple concepts to ensure quality.”
Ensuring the quality of imported components is a critical aspect of the process. Its approach involves conducting multiple proof of concepts and selecting hardware based on factors like durability, longevity and strength. Suppliers, predominantly from Europe, adhere to international automotive standards, with a minimum five-year warranty as a baseline.
The environmental benefits of solar-powered refrigeration systems are unequivocal. The elimination of diesel usage drastically reduces carbon emissions, aligning with the global push for greener practices.
As with any technology, solar-powered refrigeration systems have limitations. Battery sizing, rate constraints, and limited roof space for solar panels in smaller trucks are identified challenges. To address these, NextDrive customises designs to minimise damage risks and optimise efficiency. Hurter acknowledges ongoing technological advancements, emphasising the evolution of battery capacity and solar panel efficiency over the past six years.
Hurter believes that in time all technological challenges will be overcome. “As manufacturers of batteries, we’ve witnessed remarkable progress, especially in battery capacity. Over the past six years, there’s been a 40-45% increase in capacity, with batteries becoming physically smaller. Similarly, solar panels have evolved. We started with 250W (and we now use 420W, as this is what fits well on the trucks) though you get up to 600W now. The technology is advancing in the right direction, making it increasingly viable. For smaller units, it’s already making sense, and we’re conducting testing on larger trucks to determine feasibility. Given that it’s a hybrid system, always with diesel as a backup, it’s about fine-tuning and conducting proof of concepts to ensure practicality and efficiency.”
NextDrive collaborates with major roleplayers in refrigerated transport – Transfrig, as well as retailers such as ShopRite – which through Transfrig have integrated solar systems into approximately 90% of its fleet. Each is tailored to unique needs, and it recently assisted Checkers to roll out its first fully-electric truck. “Solar systems power critical components, showcasing substantial savings, including an annual saving of close to R60-million in diesel costs alone for ShopRite’s fleet,” explains Hurter.
He notes that on average, customers save 4.8ℓ of diesel each day per trailer, with the return on investment for a typical solar logistics investment being 1.4 years from date of installation, based only on diesel savings.
Given the extent of potential savings, he believes all refrigerated transport will ultimately go solar-powered unless physically unfeasible. “The challenges come into play with larger trucks, around 14m in length, where the battery system’s cost becomes economically challenging. Capital expenditure on solar systems must align with a sensible return on investment, factoring in financing. Another challenge is the physical weight of batteries; with larger trucks, it’s essential to consider weight limits on our roads. The concern is that adding significant weight may require reducing the truck’s cargo capacity.”
This is an industry still at the commencement of a growth phase. Regarding competition, Hurter acknowledges emerging players in South Africa-based solar logistics, but considers the current landscape a ‘blue ocean’, and one in which they have a long head-start. However, he anticipates increased interest and competition due to growing tax incentives, making their approach more compelling.
The solar incentive is contained in section 12B of the Income Tax Act, being a 125% deductible on business income tax by investing in solar.
This all means that at the moment, the bulk of NextDrive’s work consists of retrofitting. Consequently, the company specialises in augmenting various refrigeration systems, retrofitting solutions to serve as backups and eventually becoming the primary power source. However, ShopRite has also adopted a standard practice of equipping every new vehicle with its solar system, says Hurter. He adds that successful proof-of-concept trials with Food Lovers Market and in collaboration with Transfrig, have showcased the effectiveness of solar panels in powering three-phase (diesel-electric-solar) systems off the grid for a week without diesel usage.
Traditional diesel refrigeration systems are primarily being replaced by silent nitrogen refrigeration systems. Hurter adds that these units have an operating life of up to 12 years with significantly reduced maintenance and operating costs.
A solar and heavy-duty lithium battery system has been designed specifically for the needs of Coca-Cola. The system allows for the double column tail lift to operate independently from the horse, with excess solar power available for pallet jack charging and optional security systems.
NextDrive’s in-house manufacturing processes involve design of batteries, assembly and handling all wiring components. While not producing specific solar panels, the company manages wiring components and ensures automotive-rated components for reliability in vehicular applications.
The company envisions a future where technology continues to evolve, making solar-powered solutions increasingly viable. NextDrive’s focus remains on expansion, not only within South Africa but also into Africa and potentially Australia. The company sees a promising horizon for growth beyond regional boundaries, especially as the popularity of sustainable solutions continues to rise.
“We’ve facilitated the installation of charging stations for electric trucks – a part of our broader effort. We’ve tackled unique challenges, such as assisting Roto Rooter during load shedding, implementing a system that allowed their vehicles to operate seamlessly. On the design front, we’ve collaborated with Huawei on significant solar system projects, showcasing our capabilities in both implementation and design.
“In addition to our work in the transport sector, we’ve successfully implemented large-scale battery and solar systems for commercial buildings. This positions us to accommodate future needs for larger facilities, such as warehouses and factories.
“In South Africa, where we receive abundant sunlight – solar energy is a readily available option. Going green aligns with the sustainability trend, and it’s a strategic move to cut fuel and operational costs. The roof space on trucks, always exposed to sunlight, presents a practical solution.”
Maintaining optimal functionality is crucial for solar-powered refrigeration systems. Hurter highlighted a proactive approach to preventative maintenance, incorporating regular monitoring and inspections. “Monthly checks and thorough inspections every second month, coupled with continuous cleaning and optimisation of solar panels, contribute to the longevity and efficiency of the systems. The company employs on-site personnel dedicated to the continuous maintenance of solar systems for specific clients, ensuring meticulous care and attention.
Register for free to gain access the digital library for Cold Link Africa publications