looking for an inverter

I am making my own wind turbine and i estimate it will produce about 500w. I was wondering what would be a good inverter to use. I would like to tie to the grid. And should i use batterys? what are the pros and cons with using batterys if i want to tie to the grid.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: looking for an inverter

    There is supposed to be a 700 SMA Windyboy Grid Tie (Utility Interactive) inverter. But it does not appear to be a real/shipping product at this time.

    See this thread for the same question.

    Another possible issue--in general, the NEC and building departments have required UL/NRTL listing for the "things" used to make grid tied power. I do not know if you could pass a building/utility inspection for a Grid Tied home made turbine system.

    Grid Tied Inverters do not use batteries so they are cheaper and more efficient installations. However, if there is a power outage, the "standard" Grid Tied system goes "off-line" for safety reasons.

    Off Grid Inverters use batteries to supply AC power. And they cannot be connected to the grid to sell power back. In general, off-grid power (using batteries) is not cheap--Very roughly, around $0.45 per kWhr just for the inverter, wiring, and batteries (including replacement batteries every 3-10 years or so).

    Lastly, there is a Hybrid System available from several manufacturers that operates a grid tied inverter when there is grid power, and operates like a off-grid inverter when the power is down (using an internal transfer switch and batteries--more or less just like a home sized UPS system).

    You can use fewer batteries (just enough batteries for a few hours of emergency use, until the powe is back up or you turn on your generator). Saves in battery costs (fewer batteries).

    Both Xantrex and Outback (I believe) offer these systems (and other vendors too I am sure). You can read Xantrex's presentation here. The Xantrex is a large system (~4-6 kW Inverter).

    You could connect your wind turbine to the battery bank of a hybrid system and get it to do Grid Tie back through the utility lines.

    Midnite Solar is supposed to be near introducing a "MPPT" type DC solar charge controller that works with Wind Turbines. One person here has raved out about it here as over doubling the output of his wind turbine.

    I am not a big fan of wind--highly variable output (few locations are really good sites for wind), poor mechanical reliability, and sometimes expensive maintenance. So I am probably not the best person to tell you what is out there (I don't follow wind products very closely).

    I always recommend conservation as a better investment before trying other sources of RE electricity. Especially if you have utility power available.

    Have you been to the "OtherPower.com" site yet? If you are building your own--probably yes.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: looking for an inverter

    500w??????
    is that per hour? per day? per week? per month? and at what wind speed will it do this?

    i'll say in general that i'm sure you know that turbine is a renewable power source like pvs are, but this one always has to have a load on it. that means if the batteries are full and the grid goes down, you had better have another load for it or risk it self destructing. i'm not a wind expert, but in general the power it produces can be sold back to the grid and it won't generate the high voltages needed by straight gt inverters limiting your options. the need for a load at all times makes this a bit more complex than other re sources and i'll let some of those that have better advice for you add their 2 cents worth.