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I'm not sure where you're getting your information, maybe it's just out of date.

Grid-tie inverters are designed to feed power to the grid.

They automatically phase sync to the grid and automatically shutdown if if the grid shuts down. That's why they're called "grid-tie inverters".

They're available from 250 watts for a basic unit for less than $100 (made in china) up to 6000 watts with battery charger and automatic transfer switch from Outback or Xantrex for between $2000 and $5000.

So I don't know where you're getting your $20,000 to $30,000 figures.

I'm not sure where you're getting your information, maybe it's just out of date.

Grid-tie inverters are designed to feed power to the grid.

They automatically phase sync to the grid and automatically shutdown if if the grid shuts down. That's why they're called "grid-tie inverters".

They're available from 250 watts for a basic unit for less than $100 (made in china) up to 6000 watts with battery charger and automatic transfer switch from Outback or Xantrex for between $2000 and $5000.

So I don't know where you're getting your $20,000 to $30,000 figures.

" If a solar panel has less than a 25 year warranty or uses thin film in any way, shape or form, or has a negative tolerance rating of 6% or more, you won't find it on our website !"

You've got to factor in the price of complete replacecement. Hell, lets say he gets really lucky and they last 10 years..

HAHA! Twenty years if he's unlucky.

• 20-year Mnfg. warranty
• Warranties from 10 to 30 years
• Kyocera Solar Inc. KC Multi-crystalline Solar Panels 25-year power output warranty.
• Sharp ND-L3E1U 123W 12V Solar Panel 25-year limited warranty on power output.

Falcon

But the big whammy is a significant chunk of that 40gs is for the batteries which have to be replaced periodically.

Batteries? Where did he say he got batteries? I must have missed it. Doing an intertie system like he did there is no need for batteries. You only need them if you're Off The Grid. And while batteries have among to shortest warranties you can get some with 7 year warranties like Surrette batteries, 2 years full and 5 prorated. As this site says "Batteries are expensive" but only need to be replace every 7 to 10 years.

Falcon

You can try converting parts of your house to 12 or 24 volt, which would negate the need for expensive inverters and whatnot. All you'd need is a simple charging circuit for a battery (could be as simple as a diode) and then feed the 12/24 volt lights straight off it.

This is a common mistake and is only good for very low power stuff. In picking a wire size people often think going from 120 volts to 12 volts only involves the math of supplying a wire 10X larger to handle the current without overheating. In a 120 volt application, you are permitted a 5% voltage drop. This isn't much as 5% of 120 volts is only about 6 volts. No big deal when running a 1200 watt portable hair dryer. If you simply size the wire to now do the same thing on 12 volts, you no longer have a 5% voltage drop. At the same current you still have a 6 volt drop with the 10X larger wire but you now lost 50% of your power in the wire. Take a hint from the pro.. Use an inverter. The 10% the inverter lost is made up by the 45% not lost in the wire. Do the math. Engineer the project.

Either your high draw items (Microwave, toaster, blender, etc) are either within 20 inches of the battery, or you will want an inverter. With an inverter you can use standard appliances. Look for energy effecient ones.

Another item is to ditch the grid tie for small systems. It goes down with the grid providing no security. Put the critical load on an Outback inverter. It was made just for this application. Small solar, battery maitenance, load transfer to and from solar and battery, etc. You don't have a surplus to sell to the utility, so don't connect that way. Use it to supplimant your load and reduce your total load. As a bonus, you don't have to enter a grid tie agreement with the utility where they buy your power whosale and sell it back to you retail.

Find Outback stuff here;
http://www.outbackpower.com/

Disclaimer, I just use it. I am not otherwise involved with this company. The company has grid-tie stuff if you decide you really want it. I don't recommend it except for larger installations. This company has done a great job meeting the market. Their grid tie units are the first that I know of that operate instead of shutting down in the event of a blackout. They solved the number 1 problem with grid tie stuff.. blackouts.
http://www.partsonsale.com/outbackgridtie.html

I keep wondering where he got the solar system for only 3k.

Mr Solar wants $840 for 175 watts. For 1.2kw, you'd need 7 of them, or almost $6k.
He may be a tad expensive, but within reason

Add another 3k in for the inverter and other gear to hook it into your power system.

Mr Solar wants nearly 10k for a 1.4kw system.

Well, I don't really trust this site, but they're number 2 on google, $5k for a 2.4kw system, but they're advertising a $4k cash rebate and $2k california credit.

I managed to find a few links that talk about buildings that use/will use solar-powered AC, but they skim over the background: Duke | Some House

Here are are a couple of commerical solar-powered AC units: Coolmax | Solacool

You can find some more links if you google solar-powered air conditioning.

Reference: price. The raw panels are only about us$270 for 80Watt panels (new Mexico Photowatt). The regulator and wire can be used with several panels (US$500 should get you a nice 50amp regulaor, remote panel, fuses, wire, etc.).
My point: To pay CN$1000 for a single panel is pretty much a waste. You get 75/watts for US$700. For US$1000 you could have had 150 watts! One single panel has so much price overhead (the regulaor, wire, fuse, etc) that it only starts to make sense with 2 or 4 panels.
If you don't have space on top of your RV, OK - one panel - but your price is pretty much a worst case install.

I wish I had some good answers for you but I don't. I just moved into my first house and have been working toward solar power. Living in Central Florida, we have plenty of sun to spare. (Wind, too, but I'm sure the neighbors would be unhappy with a 75-foot tower in the backyard.) The question now is what am I going to do with it.

I've replaced all my incandescent lights with fluorescent. (You'll be amazed at how much flourescent lighting will save you each month. Not only does it use fewer watts, it doesn't produce nearly as much heat). I've made sure there is plenty of insulation. I'm getting rid of the electric water heater and putting in a solar version. The 15-year-old electric dryer is being replaced with a natural gas version (yes, gas is expensive but it's not nearly as pricy as electrons). There are also a few more appliances (all over ten years old) I'd like to replace but I've already blown my monetary wads so to speak.

I've been reading HomePower for inspiration and ideas. While building a solar system from scratch sounds like the best way to go about it, what I really want is a kit being that this will be my first attempt. I want parts I know will work together and a clear path to setting everything up.

I like the configuration you are proposing and your usage isn't too far out of line. (I've gotten down to 7.5 KW a day.) Most of what I've heard about Trace and Siemens is good. They both have a very loyal following.

Make sure you check out the DOE's Million Solar Roofs web site. There is lots of good information there. Specifically, they have a state-by-state incentive guide that tells what incentives are available from where and how to get your system subsidized by any number of public and private groups.

Good luck. Once you get your system up and working, I'd love for SlashDot to follow-up with you.

InitZero