The $1m laser weeder that can pay for itself within three years

Even at its $1m price tag, the breakeven on 200 acres is said to be only two or three years.

The LaserWeeder uses machine learning to identify invasive weeds among crops in milliseconds.

The LaserWeeder machine has captured the imagination of American farmers, and it has won one of this year's prestigious Artificial Intelligence Breakthrough Awards, which recognise emerging AI companies, technologies, products and services around the world.

Crop growers relish using the LaserWeeder's space-age technology to zap the hated weeds, which would otherwise be treated with herbicides, mechanically removed, or pulled by manual labourers.

Carbon Robotics in Seattle manufactures the machine and promises buyers that it will pay for itself within three years. It can be used to remove weeds from more than 40 crops; it can also be used for thinning crops.

The LaserWeeder also won the Hardware/Gadget/Robotics of the Year award in the 2023 GeekWire Awards in Seattle, described by the award judges as a self-driving robot using artificial intelligence to identify weeds in crops and zap them with precision thermal bursts from lasers.

However, the autonomously driving prototype versions were superseded in 2023 by the commercially launched version towed behind tractors. These 20-foot-wide units have three rows of 10 lasers each. Travelling at tractor speeds of up to two miles per hour, they weed up to four acres per hour. This can replace about 70 workers, on farms where the manual weeding option is used.

Work can continue through the night, thanks to the built-in lighting system. The LaserWeeder can also operate in virtually all weather conditions, with millimetre accuracy at all times.

The machines are expensive, said to have a price tag over $1m, but the waiting list for orders is said to be a year long. Even at this price, the breakeven on 200 acres is said to be only two or three years. The big price tag won't be a problem for some of the USA's 5,000 to 10,000-acre crop growers.

High-resolution cameras and computer machine learning enable it to distinguish weeds from crops in milliseconds. Then the array of high-powered lasers kills the weeds. A prototype version carrying only eight lasers could zap up to 100,000 weeds per hour.

This year, the machines will be delivered to farms across 17 US states and three provinces in Canada, with expansion into international markets planned to follow.

Carbon Robotics said it sold out of its 2021 (machine bookings exceeded $20 million in September 2021) and 2022 models.

Earlier this year, Carbon Robotics introduced a new thinning capability, using the LaserWeeder to thin for optimal crop spacing, growth and yield, in direct-seeded vegetable crops like lettuces and broccoli. All LaserWeeders have now been fitted with the software update to deliver thinning as well as weeding on each machine.

Dynamic or static banding can be set to increase speed and weeding efficiency. Dynamic banding adjusts for crooked seeding lines and for operator variability.

The software recommends the ideal tractor speed based on a desired weed kill percentage and weed type.

The LaserWeeder is fully adjustable for crop row widths from 60 to 84 inches, on a touch-screen in the tractor cab.

In the USA, the use of the LaserWeeder is permitted for organic farming, in which cost-effective weed control is one of the biggest challenges.

As well as boosting crop yields, and cutting farming costs, it supports sustainable farming with chemical-free, no-till, weed control. Lasers leave the soil microbiology undisturbed, whereas mechanical solutions can lead to topsoil loss.

LaserWeeders kill weeds in speciality row crops such as broccoli, carrots, cauliflower, chard, cilantro, kale, lettuce, onions, spinach, tomatoes, and more.

This work was once done by manual labourers, but the workers are increasingly scarce and costly in the USA.

Another important selling point is the solution to herbicide-resistant weeds, rapidly multiplying in the USA after 40 years of over-spraying.

Along with farmers, venture capital companies have been impressed by the Laserweeder. Founded in 2018, Carbon Robotics was added in 2021 to Fast Company’s annual list of Most Innovative Companies. This has helped Carbon Robotics to raise $67 million in funding. 

Voyager Capital is one of the investors, and their managing director, Erik Benson, said, "Carbon Robotics is fundamentally changing how farmers weed fields and has the potential to be this millennium’s Deere & Company.”

Meanwhile, in the EU, a grant-aided 36-month project to develop a laserweeder will end next month. After EU funding of nearly €5.5m, the WeLASER project is in its final stage of developing a technological solution to end chemical weed management.

The European Horizon 2020 innovation project is coordinated by the Spanish Council for Scientific Research, with the participation of two German laser companies, the University of Copenhagen, the Agreenculture company in France, the Co-ordinator of Farmers and Livestock Organisations in Spain), the University of Bologna, the Institute for the Ecology of Industrial Areas in Poland, the University of Ghent, and the Van den Borne Projecten company in the Netherlands.