November 11, 2013      

Company Name: Solarbrush
Founder: Ridha Azaiz
Contact: Ridha Azaiz,

Why it was founded: German entrepreneur Ridha Azaiz fell in love with solar energy as a teenager, and installed a small photovoltaic (PV) panel on his family?s balcony. To improve the efficiency of the panel, he made a small, walking robot that kept the panel clean by spraying water on the surface and swiping it clean. Several years later, as a mechanical engineering student, Azaiz discovered that it wasn?t just his panel that needed cleaning: major solar installations needed them, too. So, he returned to the problem with new ideas.

Product: Solarbrush
Available: Currently, most deployments are in the demonstration phase. The company expects to begin commercial production at his Stuttgart manufacturer by early 2014.
What it is: A lightweight mechanical robot for removing loose sand, dust and debris from large solar panel arrays
Market niche: Solar panel cleaning services and devices

Funding: Solarbrush participated in the hub:raum startup incubator, and won ?10,000 at the hy! Berlin startup competition. The company is currently in discussion with an undisclosed investor in the UK.

RBR’s Take: Global solar power more than doubled from 2010 to 2013, finally surpassing the 100-gigawatt mark. While rooftop solar has been the industry?s bread-and-butter for years, large-scale solar installations ?typically those over 50 megawatts (MW) ? are expected to drive continued growth in the sector over the coming decades. Much of this growth, today, is happening in the Middle East, Africa, and China, where an abundance of arid, desert locations offer maximum access to the sun?s intense radiation.

However, deserts have their own challenge: sand. Solar panels are only as good as their access to sunlight, and sand storms and drift have a significant impact on the total power output (and profitability) of a desert-located solar power development. Azaiz is hoping to solve that problem with his light-weight, ruggedized Solarbrush robot.

Externally, the robot is a simple, small box. It weighs just 2.5 kilograms, making it easy for maintenance workers to place the device on a panel array. Once the device is placed, it orients itself using a proprietary sensor array that detects the edges of the panel. The device stands on two legs, with suction cups at the base that can stabilize the device on panels titled at an angle as steep as 35°, making it a good fit for use in sunbelt countries in Africa, the Middle East, and arid regions of the Americas, from Arizona to Chile?s Atacama Desert.

The robot navigates a meandering path across each panel within a solar array, sweeping dirt and debris from the surface. After experimenting with multiple design options, the current Solarbrush robot moves by ?walking? across the panel using two actuators that alternatly retract and rotate. The brush stays in contact with the panel surface the entire time, and the legs retract a minimum of 3 mm toward the belly of the device to ensure that it can clear the frame of a panel.

Each Solarbrush robot costs approximately $2,000, and enables one maintenance worker to clean four times as many panels in the same amount of time. Azaiz estimates that Solarbrush could save a utility-scale 100 MW solar plant (which are typically hundreds of acres in size) about $90,000 annually, simply by reducing the labor costs required for other cleaning mechanisms and services. With literally hundreds of gigawatts of new solar power planned for countries in the company?s target markets over the next decade, Solarbrush could save the industry hundreds of millions of dollars a year all together.

Most solar-panel cleaning robots on the market are based on large-scale glass-cleaning devices, which use water for cleaning andare not easily moved between devices. Adoption for these devices has been slow, particularly in arid regions where water is a scarce resource. A growing body of data about the negative impact debris has on panel efficiency, a boom in utility-scale solar farms development in arid regions, and the work-crew friendly design of Solarbrush will speed adoption of his device.

At least two other similiar products have emerged recently? one from Japanese startup Miraikikai and Nomadd, from a Saudia Arabian research team?but Solarbrush is currently ahead in product tests and availability. Today, Solarbrush has a handful of pilot installations in the United Arab Emirates and the Americas, and it has attracted interest from a growing number of investors and partners. Azaiz was recently accepted into the Startup Chile incubator program, where he intends to focus on further product development with Chilean desalinization plants, which use solar power to make seawater potable.