Case Study:

Alternative Energy Application

Background:

With rising energy prices and the prospect of dwindling resources, solar and wind energy are some of the most popular alternatives. However even with ‘free’ fuel, alternative energy sources face many obstacles. As simply being economical is not enough, solar and wind power plants must run reliably and safely. To accomplish this Everight Position and POSITAL have worked side-by-side with developers on projects ranging from 10,000+ sensor installation to a stand-alone windturbine installed in a remote villagein Alaska that is nearly landlocked.

Challenges

In both solar and wind applications sensors are outside and exposed to the elements.To make matters worse the sensors may be in isolated locations where technicians cannot quickly or easily access them to perform repairs. Extreme high and low temperatures, rain, ice, sleet and dust must be withstood. Furthermore, recent decreases in the cost of fossil fuels has forced alternative energy to become even more economical, without sacrificing reliability.

There are several measuring and positioning tasks that must be handled efficiently in wind turbines: in addition to ensuring that the azimuth drives are able to keep the nacelle pointed into the wind, the tilt angle of the rotor blades must be monitored and continuously adjusted through a pitch control system. On top of that, speed control can be challenging under demanding environmental conditions.

Solar installations are often a case-by-case project. With a variety of different approaches, each with its own unique positioning tasks, it can be difficult to find the right sensor for a given project.

Solution:

To address these challenges, Everight Position has helped engineers in wind, photovoltaic systems and concentrated power plants (CSP, CPV)using POSITAL inclinometers and rotary encoders. POSITAL ACS inclinometers are especially appealing in solar tracking. Available with single or dual axis outputs and a wide variety of outputs (voltage, current, MODBUS RTU, CANopen, SSI) these sensors give control engineers great flexibility. In the situation a custom solution is necessary, Everight will work with POSITAL’s R+D to optimize performance while keeping costs in check. A -40⁰ to +80⁰ C operating range and a fully potted housing for IP68/69K protection make ACS inclinometers a robust solution ready for years of reliable use. For azimuth control, POSITAL UCD rotary encoders offer environmental specifications similar to that of the ACS inclinometers and numerous flange options to keep installation fast and easy.

For wind applications POSITAL UCD incremental rotary encoders may also be of interest. With a programmable output up to 16,384 pulses per revolution, these sensors are reliable, easy to use and cost-effective.

Results:

Read more about how POSITAL’s rotary encoders helped provide reliable, cost-effective electricity to a small Alaskan village here: https://issuu.com/wtwhmedia/docs/windpower_june_2015/18 .