Solar Panels - Page 2 - Contractor Talk - Professional Construction and Remodeling Forum

newenergy · 07-05-2009, 01:04 PM

I pay about 60% as much for solar panels as I did when this thread started.

Solar thermal may still pay off sooner, but photovoltaics panels last longer and require less maintenance.

**Leo G** · 07-05-2009, 01:05 PM

The panels may be nearly maintenence free, but what abou the battery system when it wears out? Big chunck of change to replace them.

newenergy · 07-05-2009, 02:40 PM

The vast majority of solar power installations now are grid-tied and don't include any batteries.

naptown CR · 07-05-2009, 02:48 PM

Quote:

Originally Posted by Leo G

The panels may be nearly maintenence free, but what abou the battery system when it wears out? Big chunck of change to replace them.

correct these batteries do cost a lot almost as much as the panels themselves in a complete system

Quote:

Originally Posted by newenergy

The vast majority of solar power installations now are grid-tied and don't include any batteries.

Yes this is the lower cost way out however will not give you power when the grid goes out unless you add the batteries and transfer switch.

newenergy · 07-05-2009, 02:52 PM

Batteries aren't a very good solution for power when the grid goes down. They sit around doing nothing except wearing out most of the time. A generator or a small UPS system is a lot more cost effective. If you are off-grid, in the mountains or something, batteries are often a lot cheaper than bringing in power or fuel for a generator.

The power goes out maybe 1hr a year or something where I live anyway. (actually, I don't think the power has gone out for a minute in the last year)

**Leo G** · 07-05-2009, 04:11 PM

So, if you have a solar voltaic system on your home that doesn't have battery storage what does it really do for you. You are usually not home during most of the efficient daylight hours. I guess that there are a few appliances like refrigerators, phones and such that need to be powered during vacant time. So I would guess that the excess power would be sold back to the power company to reduce your electric bill. Is that the main function of a power only system? I guess it would be good on weekends when you are more likely home.

newenergy · 07-05-2009, 05:05 PM

Most people (in the US) install a grid-tied, net-metering system. When you produce more than you use, like when you are at work, it turns your meter backwards, effectively selling power back to the utility. When you use more than you produce, your meter spins forwards like normal. Of course there are in between states where you may be producing 1/2 your power or w/e and you just buy less power from the utility. Also, some utilities use an additional meter and do the math instead of a meter that spins backwards.

Functionally, this is just like having a battery system where the grid works like your battery, only it is a perfectly efficient battery that doesn't cost you anything. Though, unlike a battery system, this design is not for back-up power.

As far as what power you use and when you use it, you won't notice whether there is a grid-tied solar system on a house or not - just when you see the bill.

Of course the environmental benefits don't show up in the financial calculations, but they are a big part of why a lot of people install solar.

tomstruble · 07-05-2009, 09:20 PM

http://www.solarpowerforum.net/forumVB/

this is a good place to start

Renegade 1 LI · 10-29-2009, 08:25 PM

We have started to go greener & here on Long Island the power Co. gives a rebate of 3.50 per watt plus the stae offers about 11K in rebates, This brings the out of pocket cost down to 10 - 12 K, which would mean a break even time of 5 - 7 years depending on consumption. we are working with a company that pays the up front costs & then collects the rebate money so the out of pocket cost is a lot less initially. our goal is to be able to sell a 6 - 10 KW system in the 10k range, installed.

Deckman100 · 11-12-2009, 07:47 PM

Quote:

Originally Posted by Norrrrrrrrrrrrm

I just bought a small 12-1300 sq ft house in Wilmington NC were it is very sunny for most of the year. I would like to install solar panels on the roof. Do any of you know a good rule of thumb on what sizes I should look into? Who are some good manufacturer's? Any basic prices to out for? Any particular setup? Any insight would be really helpful. Norm

Sanyo's 190-watt PV modules are an amazing 17.4% efficient. That may not sound very good, but as far as solar panels go it is well above average (12%). It costs around $1,195.

Read more: http://www.thedailygreen.com/green-h...#ixzz0WhD6IhBa

Batik · 11-15-2009, 09:23 PM

Hi guys , i will answer at first questin,,,,,
For install solar panels u absolutely dont need your sq.f of house.
U must only know how many KW u spend in 1 month .
So for example for 1200 sq.f house generally 500kw..
there are panels different sizes , but 200w panel has normal price about 5oo$.
Step 2 U must know your area insolation. In washington in summer time insolation is about 6-7 hours in day . it means u have 6 times 30 in moth = 180hours .Multiple 180 by 200w = 36000w=36Kw for 1 panel ... So u need 12 panels... 2 strings in each 6 panel , connect 6 panels in series and coneectr two strings in parallel ,,, i hope u know electrical and u can connect Panelsto DC disconect ->Inverter->AC disconect -Panelboard......

Best Regards !