The Green Transition Era: Make Money from the Sun

In this week’s newsletter, get ready to dive into the world of cutting-edge solar energy solutions from across the globe. Discover game-changing innovations and sustainable breakthroughs that are revolutionizing the future of clean energy, offering fresh insights and inspiration for a greener tomorrow.

1. Chimney Solar-Powered Agricultural Dryer

The Chimney solar-powered dryer is a sustainable solution that accelerates the drying of fruits and vegetables with high quality using solar energy. Launched in the early 2010s under the Feed the Future Innovation Lab for Horticulture program, the Chimney dryer’s smart design includes a chimney that generates a stream of hot air through the drying chamber. Utilizing natural air convection, the drying process is even and efficient, preserving the produce's color, flavor, and nutrients. Additionally, the dryer prevents insects and rain from spoiling the produce, providing farmers with greater peace of mind during storage.

Materials used for building the Chimney dryer include wood scraps, wooden or bamboo poles, transparent polyethylene (greenhouse-grade plastic), black plastic or fabric, and food-safe mesh. The dryer’s size can be customized to meet the specific needs of each user. To ensure optimal performance, the dryer should be constructed in a flat area with good sun exposure throughout its operation.

This technology has been successfully implemented in countries like the U.S., Ghana, Guinea, Kenya, Tanzania, Bangladesh, Thailand, Guatemala, and Honduras. Compared to traditional sun drying, the Chimney dryer can cut drying time in half, while minimizing the risks of mold and spoilage due to bad weather. Furthermore, it helps farmers retain the nutritional value of their products, thus increasing their market value.

In Vietnam, where post-harvest losses remain high due to a lack of modern preservation methods, the application of efficient and sustainable technologies like the Chimney solar dryer is feasible. Especially in mountainous and rural areas with difficult economic conditions and unstable electricity, the Chimney dryer could significantly reduce spoilage by utilizing solar energy. Many types of agricultural products, such as jackfruit, mango, bananas, and others, can be dried effectively, ensuring higher quality for both export and domestic markets.

With its tropical climate and abundant sunshine, Vietnam is well-positioned to adopt solar drying technology. The Chimney solar dryer not only enhances the quality of agricultural products but also contributes to improving farmers' livelihoods and fostering sustainable agricultural development.

2. Producing Food ‘from Air and Solar Energy’

Most of the food we consume today originates from plants, which use solar energy for photosynthesis—a process that converts carbon dioxide and water into molecules essential for plant growth. Solar Foods , however, has taken a different path. They use renewable electricity from solar energy to split water into hydrogen and oxygen. Then, hydrogen and oxygen are supplied to bacteria in a fermentation tank, along with carbon dioxide collected from the company's ventilation system.

Solar Foods' technology produces Solein, a protein created without traditional farming. Solein is a light yellow powder made from single-cell organisms, similar to yeast used in baking or brewing. The unique feature of this product is that it doesn’t require arable land or large amounts of water, addressing critical resource challenges faced by traditional agriculture.

The company envisions Solein being widely used in meat alternatives, cheese, milkshakes, and as an egg substitute in products like pasta and mayonnaise. In a recent trial, ravioli made with Solein-based egg replacement and a special version of cream cheese from Solein was introduced.

According to Pasi Vainikka, CEO of Solar Foods, using cellular agriculture like Solein production could help address major issues in conventional farming, such as dependence on farmland. Solein is nutrient-rich and can fully replace meat, providing a more sustainable solution for food supply. A 2021 study revealed that the greenhouse gas emissions from producing Solein are 130 times lower than producing the same amount of protein from beef in the European Union.

To scale up and realize its full potential, Solar Foods plans to expand production by 100 times the current capacity. This expansion promises to bring their technology to more markets, especially as demand for sustainable food options continues to rise.

In the context of Vietnam, where land and water resources are becoming increasingly scarce, adopting sustainable food production technologies like Solein could be a valuable solution for the future of agriculture.

3. Farm Powered by Sunlight and Seawater

Instead of land, pesticides, fossil fuels, and groundwater, Sundrop Farms operates a 20-hectare tomato farm using only solar energy and desalinated seawater. The high-tech agricultural facility in South Australia doesn’t invent new technology but combines existing ones in a novel way.

Sundrop Farms integrates solar energy and seawater to produce food in the middle of a desert without relying on non-renewable resources. Each day, seawater is pumped from Spencer Gulf, about 2 km from the tomato farm, then processed through a desalination system to produce 1 million liters of freshwater daily, used to irrigate 180,000 tomato plants in greenhouses. The desalination system runs on solar energy, with 23,000 mirrors concentrating sunlight onto a 115-meter-high tower, generating 39 megawatts (MW) of electricity per day. This immense energy output powers the desalination plant and meets the greenhouse’s electricity needs.

Water-soaked cardboard keeps the plants cool during hot months, while a solar-powered heating system stabilizes the greenhouse during winter. Meanwhile, seawater helps disinfect the air, and the tomatoes are grown in coconut husks, allowing them to thrive without pesticides. Herbicides aren’t necessary either, as workers hand-pull the weeds.

The new farm will produce over 446 million liters of freshwater annually—equivalent to the size of 180 Olympic swimming pools—and replace the need for more than 2 million liters of diesel fuel per year. Sundrop Farms is expected to produce 17,000 tons of tomatoes annually, around 13% of Australia’s market share, and will be sold at a fixed price for 10 years exclusively at Coles Supermarket. "Because we operate in a controlled environment and know exactly what the input costs are, we can offer high-quality products consistently and at optimal prices year-round," explained Philipp Saumweber, Sundrop Farms' CEO.

Reinier Wolterbeek, the Chief Technical Officer, stated that Sundrop Farms was created to address issues of food, water, and energy shortages in the face of a growing population. According to Trucost, a UK-based natural resource cost analyst, current farming practices cost the world around $3 trillion annually. On the other hand, climate change will continue to damage the resources we rely on for agriculture, while the projected population increase by 2050 will boost global food demand by 50%. These predictions highlight that sustainable and innovative farming practices, such as those implemented at Sundrop Farms, offer a promising solution to future hunger.

Sundrop Farms presents outstanding benefits in sustainable agriculture. Instead of using freshwater, the farm leverages seawater and desalination to produce clean water without chemical treatments, breaking the dependency on scarce freshwater resources. Secondly, Sundrop Farms maximizes the use of solar energy. Thanks to this renewable energy system, they can operate the greenhouses and regulate temperatures without relying on fossil fuels, thus reducing harmful CO2 emissions. Lastly, by reusing water and solar energy multiple times, Sundrop Farms keeps product prices low, directly benefiting consumers by lowering production costs for water and electricity, making their products more affordable.

Vietnam holds significant potential for adopting sustainable agricultural models like Sundrop Farms. With its long coastline, Vietnam can fully harness abundant seawater resources, combined with desalination technology, to support agriculture, especially in arid regions and islands where freshwater is scarce. Furthermore, solar energy is a rich natural resource in Vietnam, particularly in the central and southern provinces, where sunlight hours are high year-round. Applying solar energy in farm operations not only reduces production costs but also helps protect the environment by cutting CO2 emissions. This aligns with Vietnam’s goals for sustainable, clean agriculture and its export-oriented development strategies.

4. Solar-powered Freshwater Filtration Device

Desolenator has successfully developed a desalination and water filtration system that runs entirely on solar energy, a breakthrough solution for the global water scarcity issue. This system combines distillation and thermal filtration processes to produce drinking water from seawater, brackish water, or polluted water at a low cost.

The device consists of an inclined surface covered with solar cells, and its mobility is enhanced by terrain wheels. It is far more efficient than traditional desalination methods like reverse osmosis. Moreover, the device is self-sustaining, needing no fossil fuels to operate.

Each unit can produce up to 15 liters of fresh water per day. Desolenator’s technology significantly reduces CO2 emissions compared to conventional desalination methods and can provide clean water for up to 1 billion people in water-scarce regions.

William Janssen, founder of Desolenator, stated: “We anticipate that this new technology will be suitable for any country facing water scarcity, including Somalia, Peru, Chile, the Philippines, and many nations in the Middle East.”

With its long coastline and numerous regions struggling with saltwater intrusion and water shortages, especially in the Mekong Delta, Vietnam stands to benefit greatly from this technology. Desolenator can provide clean water to coastal and rural areas without relying on municipal water systems or power grids, helping to mitigate the impacts of climate change and saltwater intrusion on the local population.