NGC-Solar power

[redrider]

Had a visit from a Sunrun rep. Did some research. Any one here using solar panels for their home or business and any problems?

[Triple Jim]

I have a solar powered pontoon boat and a solar panel on the roof of my van.  Not large scale, but they've been totally reliable for six or eight years.

What kind of deal on what kind of system are you considering?  I'm always interested in solar power, especially when it becomes competitive with commercial power.

[Perazzimx14]

Photovoltaic or evacuated tube?

4 years ago my company installed the 3 largest (at the time) evacuated tube system in the country. This was done when there were lots of government credits data and buying power was great do to the size of the project. The system actually out performs the initial s given by the manufacturer. I could have bought a solar package for my house to heat all my hot water and supplement the heating system. At the time even with Government credits ability to buy are a wholesale level it was still cost prohibitive. Solar is coming along and someday will potentially be worth while and feasible but for now it is still "feel good"  form of energy production. Now that crude is at record lows, discovery of huge reserves of domestic oil/NG and cheap foreign oil solar is even less feasible.

The biggest problem with evacuated tube hot water systems are you cannot turn the sun off. So one of several thing needs to happen:

1. Large enough reservoir to collect and hold more hot water the sun can produce in a given day. "filled system".
2. Have a heat sink that will exhaust excess heat so the system will not flash to steam. Typically done with e radiator and fan (uses energy to turn the fan so is counter productive) or a heat exchanger and domestic water dumped to drain (another waste of resources)
3. Install a drain back system so that when the reservoir reaches 212* the system shuts off and the water drains back away from the collection bulb headers. Unfortunately once the the system reaches 212* it needs to be turned off and locked out from further energy collection until nightfall. You cannot turn water back into the system when the collection bulbs are hot (anytime the sun is up)or it will flash to steam and destroy the system.

Photovoltaic has its issues as well. Battery banks and power inverter(s) are expensive.

It would be interesting to hear what promises did the solar salesman make you.


 

[canuguzzi]

Properly sized and installed, you can get your costs for electricity to zero. There will be the initial ROI period to offset the purchase price (don't lease it) but done right and if you have enough exposure to the sun it can be a zero cost all the way around.

You do not need batteries unless you want to go off grid. A grid tied system is best for the typical home owner.

A lot of it depends on where you live and what you power in electric. A/C units and heaters aren't a practical target for solar panel installs. Almost everything  else is.

What you end up doing is selling the harvest to the utility at wholesale which offsets your retail purchase of electricity. A well planned system will harvest more than you use so that even at wholesale, your contribution is so much greater than your use, it costs you zip for utility electric.

Some utilities are allowed to impose distribution charges since there is a cost to take the electric you contribute and use it in the grid.

The big question is how much do you pay for electric (total) each month and what is your expected solar energy harvest. Those things should be clearly spelled out because they are known things. You can easily do the calculations yourself.

I designed and built solar arrays with automated tracking systems, lived off grid for nearly 5 years. If you need some resources to help you decide, PM me and I'll load you up. It isn't rocket science and figuring out if it will really benefit you isn't very difficult.

[Perazzimx14]

NP,

Why did you give up living off the grid?

[Bisbonian]

We have 10 panels on a grid tied system.

We haven't paid for any actual electricity in 2 years, but the power company still hits us up for administrative fees.

In addition to our home, we have a plugin hybrid car that gets charged off the solar.

[redrider]

Wow. Thanks for the replies! The system is linked to the grid with SCE&G paying me for the solar power generated but not used. Sunrun is the company.

[canuguzzi]

NP,

Why did you give up living off the grid?

Moved.

I am now in the process of getting the house ready for as off-grid as possible (will still need water). In a temperate climate there is no need for A/C and we use very little heat. By next year this time, everything but water will be off-grid.

Storage will be AGM batteries and a 3500 watt inverter will take care of the house. It is pretty easy to do, just takes a bit of planning. With trackers you need less than half the panels as opposed to just sticking them on the roof or static on the ground.

[Semper-guzzi]

My FIL sells solar. We got hooked up. I pay like 80 cents a month for admin fees for electricity. The sun takes care of the rest. Not too shabby. Deinitly don't lease it.

[Doppelgaenger]

I ran a solar power system for a few years. We started off-grid and eventually move to grid-tie as you're describing.

The main PITA is battery systems, you need to stay on top of them as far as equalizing goes if you get batteries, if not then it's pretty straightforward.
Single axis adjustment (winter and summer angles) are  worth the time, but 2 axis tracking is not.

[wavedog]

I lived completely off the power grid for six years in Arizona. Had a house and five acres out in the desert and no power lines within 13 miles. Had a well 900 feet deep with a 5500 gal water tank and a 13kw diesel gen to pump water to the tank. DC powered pumps and water pressure tanks provided pressurized running water for the house and land. A solar preheater on the roof for hot water. There was a propane hot water heater but eight months out of the year I didn't need it. It was an interesting way to live. I know that technology has gotten better since then. It was not cheap to live with solar power. Batteries - the good ones - are expensive. You will pay for electricity either way by a monthly bill to the power company or a huge amount up front to buy your solar equipment. Spread it out over 10 to 15 years and it may be a wash.

[canuguzzi]

I ran a solar power system for a few years. We started off-grid and eventually move to grid-tie as you're describing.

The main PITA is battery systems, you need to stay on top of them as far as equalizing goes if you get batteries, if not then it's pretty straightforward.
Single axis adjustment (winter and summer angles) are  worth the time, but 2 axis tracking is not.

With good AGM batteries, they rarely need equalizing. The flooded batteries are old school, new installs rarely use them unless the design isn't keeping up with the times.

The trick is tonuse good equipment, properly design for the system and the maintenance is practically zero except for the once in a great while battery replacement.

2 axis tracking is a proven design and harvests a far greater amount of energy than so gle axis and is indeed worth it. The technology is readily available and and as zero maintenance as you can get.

Like a lot of things, there is the old way and new way if doing things and here what was a good way just 10 years ago is obsolete today.

In the winter and higher latitudes dual axis trackers far outperform static panels. Its a scientific fact.