Camarillo’s Power-One transforms renewable energy
By Bridgeman Carney 10/10/2013
In our own communities we have seen continued growth of solar panels atop home rooftops and commercial buildings and the emergence of low-wind turbines that will soon also be on rooftops and buildings. Let’s look at how the power they generate actually gets transformed to power we can use.
Solar panel and wind turbine systems actually generate DC (direct current) voltages, which are like the power found in batteries in that they are polarized. That is, they have a positive (+) and negative (-) as they have a specific direction to their power flow. If you put a battery in backward in your alarm clock or portable radio, it doesn’t work because the circuitry is based on the + of the battery going to the + terminal of your device and the - going to the -.
Our homes and offices, however, use AC (alternating current). Devices designed to use AC electricity (almost every appliance you have — air conditioners, lights and so on) do not care, for the most part, about the orientation of the two wires when plugged into the wall.
So how do solar and wind DC power play into the grid of our AC power use? Now, this is where the Ventura County-based Power-One comes into our story. Power-One — a member of the ABB group, a global leader in power and automation technologies — designs, manufactures and provides inverters to an ever more power-consuming world, and moves more to local renewable, sun and wind energy sources. Power-One’s Aurora products connect the power from the solar and wind systems to the public utility power grid in what is known as a GTI (grid-tie interface) system.
An inverter is an electrical and electronic device that transforms or, if you will, “inverts” DC power to AC power. This is actually a lot more of a challenge than you might think.
First, solar and wind systems come in a wide variety of power-producing capabilities. Each system can generate from zero volts up to high-DC voltage levels. It also produces from zero to high-level amps. The basis of our power, such as we see on our electric bills each month, is watts. The basic electrical equation is that you multiply volts X amps = watts. So if a wind turbine is generating, say, 180 volts and 10 amps, it is making 1,800 watts. That’s a lot of power to handle. Power-One has been designing and producing its Aurora line of GTIs for some time, just for this purpose.
Secondly, in order to push this power onto the grid or to a home connected to the grid, the requirements of public utilities for clean AC power (which, as mentioned earlier, is what we use in our homes and offices) are very specific. Should a GTI device such as the Aurora not do its job properly, it would cause problems for other users in the area. The Aurora is a gatekeeper and must also be able to cut off, pushing surplus power into the utility grid in the event the grid itself has a power outage. Having a solar or wind system pumping power into a grid while utility personnel are working on the grid to fix problems would be very hazardous, so the Aurora products prevent such a circumstance from occurring through better designs and redundant internal systems to serve as its own backup.
Power-One was founded in 1973, according to the website www.findthecompany.com, and is a long-time Ventura County technology resident. The headquarters and research offices are located on Calle Plano off Pleasant Valley Road in Camarillo. Demonstrating how renewable energy is growing in Ventura County, some of Power-One’s neighbors in the immediate area include SolarWorld, a major provider of solar systems, and Sauer Energy, an emerging low-wind turbine systems provider.
This month ABB, a Swiss-based global leader in power and automation technologies with more than 145,000 employees, completed its purchase of Power-One, which will provide further resources and international exposure to Power-One.
Plugged In is a monthly column focused on new technology in and around Ventura County and it will be featured the second week of every month. Plugged In authors Bridge Carney and Karl Geiger are chairman and past chairman, respectively, for the Ventura Section of the Institute of Electrical and Electronics Engineers [IEEE], the world’s largest professional organization, with more than 800 local members in Ventura County. Please find them at www.ieee-bv.org.