Gotcha.
That's the one near Vesta. I assume that machine is running away (brake failure) since the last couple times I've drove past it had at least 2 of the 3 blade tips deployed due to overspeed. The 4 just south of Marshall near Lynd met their demise when the owner fiberglassed the deployable tips "closed" and the machines had no overspeed protection whatsoever. It was like watching fish get shot in a barrel- which one was next to jump the tower in the next thunderstorm. All 4 are gone now. There were about a half dozen or so installed near Tyler and most have either self destructed or have been taken down after not running for years. One was recently replaced with an Xzeres 442 10kW machine on the 'Harvester tower; looks to be a good install.
I do really like the little Enertech machines though. I may be biased since I own one and flew one for quite a number of years, but they are really simple 'work-horse' turbines. Off-the-shelf motor coupled to an off-the-shelf gearbox with blades. The small units varied by what they used for braking. Mine is a 1500 which used a mechanical brake between the motor and gearbox. It was a Reliance Unibrake if I remember right. The 1800 was the same machine with a boasted output rating to 1800 watts and an upgraded hydraulic brake system. It had a hydraulic pump and reservoir which were mechanically attached to the motor and the hydraulics would run open circuit until power was cut to the turbine, at which point a solenoid valve would close and force the pump to pump oil against a relief valve. The relief valve was set high enough that the pump would exert enough resistance to bring the rotor to a stop. It was a lot smoother and gentler on the drivetrain compared to the mechanical brake which would slam to a stop within a few rotor revolutions every time the brake applied. Power was cut to the machines at low winds to prevent them from continuing to motor and draw power below cut-in speed or they were also disconnected in high winds as a high wind shut down to stop the machine in a storm. When the power was cut, the brake system would engage at the same time, hence the reason for the change to the 'softer stopping' hydraulic system on the 1800. Imagine how many times the turbine could motor up to speed and then 5 minutes later, slam the brake on in a marginal wind day. Lots, trust me! Never did hear of anyone who was bold enough to try and run one of the little Enertechs with a grid interactive inverter, but the idea has been kicked around before. Big dollars there to possible have a mishap with...even if the machine is free and you rebuild it yourself. Personally, I don't think the little Enertech turbines will run very well on a battery based inverter. Too much chance of the frequency or voltage being pushed out-of-wack causing an overspeed of the machine. Keep in mind- these were dowwind, fixed pitch turbines that relied on a stiff source of grid power for power and speed control. Stall was all that they relied on. No load = no stall + no furling = airplane on the top of the tower = very unhappy guy who put big bucks into getting it set up to have it explode, possibly wrecking the tower in the process. Some of the later units had tip brakes in case of a brake or gearbox failure, but at that point, they would 'maybe' keep the thing from self destructing. Mine had them, but were a pain to keep set correctly with ice and what-not bending them in the winter months. Overall, too big of risk to try and run on an inverter if you ask me. It's not what the turbine was designed for and the time, effort and same amount of cash could easily be put into a turbine that can be used as it was intended to do.
Corey
