[Editor's note: Kiril Lozanov, CEO of Capital City Renewables, is the husband of author Sarah Lozanova. Capital City Renewables installed the aluminum lattice meteorological tower that is the subject of this article.]
In recent years, wind turbine technology has advanced considerably, with many onshore industrial-scale wind turbines in the U.S. now standing at 100 meters and capable of powering more than 1,000 households.
Although turbines have advanced greatly, the wind assessment technologies used to determine if a site has suitable wind resources and is economically viable have not kept pace. A recent development, however, is boosting wind data quality, while also reducing the environmental impact and cost of wind data collection.
Capital City Renewables recently installed a 100-meter aluminum lattice meteorological tower in Colorado, the second tower of its kind in North America. It is unique in that it is made of aluminum, instead of steel, and mounted on a steel plate, rather than a cement pad. It can also be climbed and easily moved by tilting it down. This tower lets wind developers assess wind resources at various heights, including at the hub and the turbine off the ground, not including the blades.
The tower was specifically designed to meet the needs of the wind energy industry, a relatively new industry that is struggling to assess wind resources at increasing heights. The majority of the hub-height towers currently in use by wind energy developers were designed for the communications industry. Although they are proven reliable, the needs of the two industries are different. This results in wasteful practices that are both expensive and resource intensive.
"Communication towers are designed to remain in a given location for decades and the weight of 100-meter steel lattice towers requires them to be mounted on cement," says Kiril Lozanov, CEO of CCR. "These towers are really cumbersome to install and wind developers usually scrap them after just one use, instead of moving them to a new project. This is a wasteful practice that doesn't allow developers to make good use of their assets. The wind energy industry generally uses meteorological towers for one to three years per project during the pre-construction phase, so our structures do not need to be permanent."
A 100-meter steel tower with equipment costs between $160,000 and $200,000 to install, maintain and remove, according to Lozanov. In contrast, an aluminum lattice tower costs between $120,000 and $130,000, and much of the tower can more easily be reused. He estimates it can be utilized and moved to a new location up to 10 times, although it hasn't been achieved yet because it is a new product.
It is also less complicated to install a tower on a steel plate than cement pad. "It's easier to approach a landowner to receive permission to mount a tower on a steel plate," says Lewis Gunn, director of operations for Baseline Renewables. "A lot of farmers don't want concrete going into their land and some of it usually gets left behind once the tower is removed. Typically the cement is removed only to the depth specified in the lease."
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