Is this a silly idea?

[hat_man]

Hello everyone.

I am new to this section of the forum but have been posting on the automotive side for a while. I had thought about solar and wind turbines for home use and had seen different articles about how some lucky people could actually get their electric meters to "spin backwards" because they were making more juice than they were using. they could then re-sell the "overage" back to the electric utility for a lower rate (IIRC) than they were already buying it for but still saving money on their bill.

My idea was, if yo are going to all the trouble of adding solar and possibly wind then why not add a battery bank (outside the home of course for venting purposes) and another panel to run low draw items such as lighting. That is if you are using CFL or LED bulbs or even possibly using 12v DC bulbs you can find at the RV dealers.

The other idea was to convert the battery bank output to 120v AC and run wire to one half of certain outlets in the home. Some of the stuff we plug in are low draw like alarm clocks reading lamps (with low draw bulbs) phone chargers etc. Why tie this system into the "grid" and re-sell your hard work back to the utility for a lower rate than they charge you when you could use "your" power yourself at 100% savings. Minus the cost of installation of course, but if you are going wind/solar you will already have initial costs anyhow. You'd only be paying the utility for the electricity your high draw items make.

I know there could be some code issues with power from two separately derived systems in the same conduit or box, but if that is the case then just pipe in 2 systems and keep them separate. Of course this would work better on new construction or a total home rip out and remodel.

Is it a silly idea to NOT tie a solar/wind system to the grid? I can't see where the electric utility could complain too much. The water company can't complain if I use collection barrels for some of my water if I am tied to their system and the gas company can't complain if I decide to heat my house on a hybrid geothermal/natural gas system. Why not a hybrid "natural"/utility electrical system?

[user removed]

It would make sense if a significant portion of your generation was going back to the utility company, only to be resold to you at some other point in time. You will have storage cost as well as storage losses to consider in your calculations.

regards
Mech

[Frank Lee]

I use about 100-120 kwH/mo. but with the ****headed regressive billing structure my COOP has, more than half my monthly bill is for the service fee. Even if I were to generate 100% of my power but stay on the grid- for backup or ?- I would only reduce my current (PUN!) bill by less than 50%, or $20-$25/mo.

[justme1969]

Dont let a Solar salesman talk you into less or more than you need is first rule!

My first idea was to convert the battery bank output to 120v AC and run wire to one half of special outlets in the home. There are alot of different plug end configurations you can get two visually separate systems.

*** Why tie this system into the "grid" and re-sell your hard work back to the utility for a lower rate than they charge *****

Yes that is your best bet use the calculator to add up all systems and factor in a loss of 6% over then build a system that matches your needs.
Or just build enough that you can run some system with it and from batteries Be it lighting or an a/c unit etc. on a designated circuit.
I like the plan to run hall lighting and mabe electric dryer off solar and small windmill, while providing heat or A/C for season use. It is simple to get into and your capable of building up afterwards to more.
Like I said if outlets are added use a t set up plug and receptical for low amperage items that will be allowed in it. or even an inverse prong, there are many configurations beyond the 2 straight slots and a d hole.

I augmented my electric water heater with 2 150, connected well pipes coiled over my back roof. I thought it was going to be a minor expense but add up water grade fittings to bypass into water heater drain from my out back faucett and hose to pipe conversions and hooks to lace it on the roof Ive got 100 bucks into it. I was proud of the system untill I realised that the water was static most of the day and electric was still heating it insid ever so little. Now I need to purchase a circulator or install water heater timer to shut it off. I like circulator alot but there is more expense there and I dont have base board heaters to utilize its other benefit.
Electric bill has dropped $17 a month though and it has nearly paid itself off.
would do better if the kids would bathe from 2 - 6 pm in over 1/2 hour intervals, but thier not into my eco home stuff so much as I.
I am thinking of lacing another 150 feet into it also to get more solar duty from it.
The 1" pipe is cool to touch into water heater after 12 minutes of my eldest son bathing.
yep looks a sauna when he comes out I cant wait till he pays for his own utillities hehehe 2 more years I keep reminding myself.

[justme1969]

This is a fair company Im not saying best but fair and knowledgable.
¤ Discount Solar: Your source for low cost, high quality solar panels

[RedDevil]

Storing excess power in batteries is no solution.
Just today I looked into some LiFePo4 batteries; one unit, 12.8V by 40 Ah including BMS looked promising. Could store half a kWh. Could have 2000 charge cycles. Did cost more than 1.000 kWh would cost, and thats without the DC/AC conversion.
So there you have it; storing energy is good for power outages, but not for saving on total cost.

You can try to match your demand to your production, by having twin thermostat settings on your boiler or fridge, to make them work harder when you have an overage.
Or a smart use mode for the home A/C. Could be a nice Arduino project balancing them all. Well you get the idea.

[Occasionally6]

If you are going to have two separate circuits is there any reason why one of them couldn't be low voltage DC?

A lot of the things we use electricity for already drop the AC mains voltage down to either 12V or 5V DC. PC's run off 12V DC (with an internal voltage regulator) phones and 'i' devices charge at 5V, some of the less expensive TV's run off 12V with a regulator in the power cord.

That would make it safe to DIY and make it clear which devices were running off the PV cells. It would require distinctly different wall sockets so as to avoid confusion and plugging in a 12V device into 110AC.

[redpoint5]

Battery storage systems make sense only for those who cannot be served by the grid.

Many utilities use "Net Metering", which means your electric meter runs backwards during periods of overproduction, and forward when drawing more than can be generated. You pay the net difference. That is, you pay only for the amount of electricity used over the amount generated by the PV, Wind, etc. This means you are "paid" the full rate for the excess energy generated. Utilities will often limit the amount of energy they will credit you, to the amount actually consumed. Some may pay you at a reduced rate for any excess over the amount consumed.

From a financial and environmental standpoint, battery storage on a grid-intertied system is a bad idea. Remember that batteries are a consumable item that will need replacing, and that charging/discharging them reduces overall system efficiency. Selling energy back to the grid is more efficient, and acts like a battery. You "charge" the grid when producing more than you need, and "drain" the grid when the demands are higher.

A smart setup would size the renewable energy system to produce 100% of the energy consumed in the lowest consumption month. This would theoretically result in 1 month where the electric bill is zero, and all the other months are considerably reduced.

[Frank Lee]

Ha Ha "electric bill is zero"- I think not. See my previous post.

[RedDevil]

The infrastructure need be there even if you give back just as much as you take. You do use it, your life would be worse if it weren't there.
Just like you do get a phone bill even if you don't make calls at all.

Suppose you have a shop on wheels in a rural area. You build up a client group, drive by their homes every day.
Some of them just look at your stuff but seldom buy anything. Would you keep turning up at their place every day for no charge at all? You'd lose big time on them.
And what will you do if they do take stuff off your hands when they need it, but bring it back a few days later and demand a full refund, time and time again?