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Thread: Programs Let Homes Produce Green Power .... electricity meter runs backward

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    Default Programs Let Homes Produce Green Power .... electricity meter runs backward

    Programs Let Homes Produce Green Power

    "When the sun shines bright on their home in New York's Hudson Valley, John and Anna Bagnall live out a homeowner's fantasy. Their electricity meter runs backward.

    Solar panels on their barn roof can often provide enough for all their electricity needs. Sometimes - and this is the best part - their solar setup actually pushes power back into the system. The Bagnalls "net meter," a state-sanctioned setup that allows homeowners to adopt renewable energy without taking the more radical step of disconnecting from their local electric utility, Central Hudson Gas & Electric.

    Net metering essentially allows people to become mini-power producers. Programs vary state to state, but they are typically coupled with financial incentives that make it easier to invest thousands of dollars for photovoltaic panels, windmills or fuel cells. Since sun and wind are intermittent, customers still rely on the grid for steady service. The meter runs backward when more energy is produced than a customer consumes.

    "When they first put this in, it ran backward more than forward," said John Bagnall, standing by a meter on a winter morning. "Even with a hazy sun ... we're producing electricity."

    Advocates see net metering as an environmental twofer: it promotes green energy and reduces the strain on the power grid. But the number of people investing in solar panels or wind turbines has been relatively small so far, despite the selling point of being able to turn the table on electric utilities.

    Federal legislation requires states to consider adopting net metering standards by 2008, though programs are already in place in more than 40 states, according to the Interstate Renewable Energy Council. California is king when it comes to net metering, accounting for 86 percent of the 15,200 customers tallied nationwide in 2004 by the Network for New Energy Choices, a New York City-based renewable energy advocacy group."

    http://ibtimes.com/services/pop_prin...id=17631&tb=bh

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    And in California, those people only account for about 0.5% of the electrical power consumed in the state. And 0.5% was the limit (net metering program was about to close because it filling up--now law has been rewritten to up that limit to 1.5% of grid power).

    Still a long way to go...

    -Bill

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Already happening here in Australia, but the investment needed to generate more than you use is around A$20,000.
    Norm

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Norm, use less electricity and you can get the equipment for less than 10K$ -- that's what I've been using for the past 10-plus years..

    btw those Outback mppt units are great -- I have never gotten so much power out of my array -- the batteries are full by noon, so the rest of the day's sun is gravy for espresso (so to speak) and TV or pumping the well...

    it allowed me to rewire the panels for 48 volts and then the outback converts it back to 12 volts for the battery bank..and readouts for everything! ..I could go on..

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    I think that because Norm is in Australia, his prices down there are pretty close to twice the $10k USD prices in the US. Or $20k AusDollar.

    -Bill

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward


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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    ted, how's about a few pic's of your setup?

    we sure love to see one in action!!!

    Quote Originally Posted by TedTheLed
    Norm, use less electricity and you can get the equipment for less than 10K$ -- that's what I've been using for the past 10-plus years..

    btw those Outback mppt units are great -- I have never gotten so much power out of my array -- the batteries are full by noon, so the rest of the day's sun is gravy for espresso (so to speak) and TV or pumping the well...

    it allowed me to rewire the panels for 48 volts and then the outback converts it back to 12 volts for the battery bank..and readouts for everything! ..I could go on..

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    I don't yet own a digital camera! :

    ..was reading attentively about the Nikons D-200 and D-80..then I hear of something coming better down the road, and I wait -- this has been going on for a few years now...

    what's to see is: 12 Siemens (now Shell) 75 watt panels on a passive Zomeworks tracker..a Trace 2512 sinewave inverter, that Outback controller, and 16 MK agm 200 ah 6 volt batteries.. that's all you need...

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    I've got a 3,000 watt inverter and nothing else from your list.

    sure would like to get set up with a few panels... pretty large up front costs...

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    yeah, and the weakest link are the batteries, depending on how many you get and well you use them, they will eventually need replacement -- they can easily last 3 years, 10 or more if you invest in a large industrial-type battery bank..
    hopefully soon there will be new better ways of storing the daylight energy, like flywheels (see the Beacon) -- getting smaller, but they are still too large for home use..

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Here's my system. I'm off grid, but my inverter could put more power into the grid than I use over the course of the year. The big bank of panels is mounted on a passive tracker. The panels produce about 80 percent of the power I use over the course of a year. The wind generator about 5 percent. A propane generator provides the rest.


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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Josey, WOW... that looks like a sweet setup!

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Quote Originally Posted by TedTheLed
    yeah, and the weakest link are the batteries, depending on how many you get and well you use them, they will eventually need replacement -- they can easily last 3 years, 10 or more if you invest in a large industrial-type battery bank..
    hopefully soon there will be new better ways of storing the daylight energy, like flywheels (see the Beacon) -- getting smaller, but they are still too large for home use..
    Properly sized and maintained batteries last 15 years or more. The key is that they do need to be the right size for your use and they do need to be maintained. The homepower newsgroups ( nntp://alt.energy.homepower ) talk about proper depth of discharge and leveling procedures a lot.

    Daniel
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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    stupid question... but if you are allowed to give back to grid at retail prices, then pull power as you need it.

    would that not act as a giant battery and/or have the net effect as having giant batteries.

    seems utility companies would love this as your contributions would occur at sunny periods and help relieve peak loads. you would then pull back out at off peak periods.

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    You're right, Cy. The nice thing for people on grid is that the grid does become their battery. The drawback is that they lose power when the grid goes down, which it did out here in NW Washington a lot this winter. However, for people off grid, like me, we end up wasting most of the power we generate during the summer because once our batteries fill up, there's no where to put the excess. Plus, batteries are inefficient. We lose maybe 15 percent of the power we put into and pull out of the batteries.

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    that's why I'm trying AGM batteries this time around -- I used up 14 pairs (250 ah Trojan J-250) of 6 volt wet-cells last year, they lasted over 5-6 years, probably would have lasted longer if I had a 'pwm' type (like the Outback) controller for them, and hadn't been late for an electrolyte top-off once or twice..I even lost a couple pairs to the dreaded 'thermal runaway' .. but the AGMs are supposed to be immune to that, and they are about 15-20% more efficient than wet-cells, that is; they absorb the energy faster, and give it up more easily.. I got only 16 pairs of 200 ah 6 volt AGMs this time, figuring i could keep them filled more easily -- and so far they are depleted only about 25% in the morning..

    and..no more 84 little caps to unscrew, top off with water, and screw back every few months..the AGMs are maintenance free; no acid fumes to corrode the terminals, no periodic washing.. I'll see how long they last..one more thing that swayed me to the AGMs ; free delivery to my house! ($160.20 each)
    Last edited by TedTheLed; 01-24-2007 at 09:31 AM.

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    The utilities make money selling power--they do not make money selling and buying power at retail (net metering at retail rates is another government mandated customer subsidy).

    In California, during parts of the year, the peak power is now happening around 6-9pm (California Daily power usage/forecast--updated every minute or so)--obviously when solar is not available.

    Also, I was reading about Germany's experience with wind power. Their issue is that current wind power grid tie interfaces are very finicky regarding power quality. If there is a few cycles of power quality problems (transmission line short or other fault anywhere on the grid), the interfaces were designed to drop off line (anti-islanding per law), utility generation plants are designed to ride through short sags. Also, wind is variable so they cannot predict how much minimum power will be available over time... All that adds up to the requirement that 90% of online wind power needs to be backed up by hot standby generators (or generators running a few 10% below capacity--utilities normally only run about 10%-50% standby capacity).

    Some of these issues can be resolved--and others cannot.

    Regarding loss of power and solar--I to looked at this when thinking of buying grid tie with or without off-grid capability. I decided to go with a small Honda 2kW eu2000i generator as backup (last power failure here more than an hour or so long was 50+ years ago)--was cheaper, portable, and more efficient (batteries are ~80% (flooded cell)-90% (AGM) energy efficient). And once you choose grid tie only inverter, the solar electric panels voltages are too high to work with any battery solar charge controller (Grid Tie usually require 170-200 VDC or more minimum--solar chargers are 150 VDC or less maximum).

    -Bill

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    *Flashaholic* Brock's Avatar
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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Our system is relatively small, four KC 120's, an outback MX-60, eight 8A8D AGM's (12v at 2000A) or 24kw and stacked Trace SW2512's. I wish I had gone with a 48v system from the get go, you live and learn. I also wish I could cut down my neighbor’s tress to the south to get more sun I have a bit more about my system at
    http://www.uwgb.edu/nevermab/solar.htm
    Brock - Used to have some web sites

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    Brock, how many volts into the OutbacK?

    (I was also foolish to not wire the array for a higher voltage at the beginning, 12 volts requires so much heavier cabling!! now it's 48v. and I'm getting more amps out of it..)

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    Default Re: Programs Let Homes Produce Green Power .... electricity meter runs backward

    I have the array set for 24v. I did try 48v as well in to the outback feeding the 12v battery bank. The problem was the MX-60 likes to see 5+ amps on the input side to go in to some more efficient conversion mode. If I am set for 48v I often would see just about 5 amps in the morning and evening. I switched back to 24v array and got about 5% more so I have left it that way. My plan is to add another 4 KC130's and at that point I will go to 48v to avoid more line loss to the MX-60.
    Brock - Used to have some web sites

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