Author Archives: mogens

Solar Trackers & Reliability

Looking at a solar tracker, and one sees a simple mechanical structure. Probably something anybody could build? Now add to that a requirement for it to operate over a 20 year lifespan, and the picture has quickly changed. Try to think of a electrical/mechanical structure which has operated non-stop, during all types of weather, for the last 20 years.

When designing and building a solar tracker, a goal of 20 year operational life must be considered because the additional performance gain can quickly erode with unexpected maintenance costs. Baring lightning or other extreme power surges, the electronics and software will easily last 20 years when designed correctly. The main problems are mechanical, gears, motors and bearings.

If you are about to venture out and design a new solar tracker, please give us a call to discuss your options. With our remote managed controllers, we see the day-to-day operational troubles, and have helped many tracker manufacturers improve their designs. There’s no need to retry paths leading to troublesome designs.

A Local Content Perspective; why Solar Trackers?

We often hear solar PV systems promote job growth, but conveniently overlook where the bulk of capital is flowing. Solar PV modules, inverters, and racking systems all consume the lion’s share of a solar system’s capital investment. Adding a solar tracking system, can increase a solar system’s energy yield by as much as 45% or higher, while also benefiting the local economy. Most solar trackers can be designed by local machine or steel fabrication shops – thereby increasing local content. The additional Operational & Maintenance effort, usually reduced to an annual lubrication visit, also increases the local labor component.

A Grid Perspective; why Solar Trackers?

Dual Axis Tracking vs. Stationary

Despite the continued downward solar PV module price pressure, Solar trackers will remain an important component in tomorrow’s energy systems because of the sustained daily power curve.

With stationary solar PV systems, a daily bell shaped power curve is produced with maximum power produced at noon. As a result, a the power grid will have to be engineered to distribute the momentary noon time power production. A poor cost/benefit proposition.

Solar tracking systems will, because of the sustained power curve, provide the grid with a sustained power curve throughout the day. As a result, possibly little to no additional engineering efforts will have to be made to the grid.

It is the cost/benefit proposition from the grid’s perspective which will drive the need for future tracking systems, and this is something we will see in the way Power Purchase Agreements are about to be negotiated.

Global Warming; Greenland 2012


South East Greenland, July 2012

Anyone traveling from Europe and to the US will inevitably cross Greenland. If you are lucky, the weather will be clear, and you can because of the low humidity see for 100’s of miles. Such was the case when I first flew from Copenhagen to JFK/New York in August 1979. Approaching Greenland, an entirely white landscape unfolded dotted with floating icebergs.

On a recent return trip in July 2012, my path was roughly the same. To my astonishment I saw barely any icebergs, and large swaths of coastline with nothing but exposed bedrock. Continuing inland, there were long stretchmarks in the ice. A week after my arrival, we could in the news read about massive ice melts and flooding in Greenland.