Prev: Lost online payees on year-end operation
Next: Has QD2010 changed how reports get customized?
From: Sharx35 on 9 May 2010 02:50


"Ken" <jkbecker(a)no.spam.opt.opline.net> wrote in message
news:4be635a5$0$21968$607ed4bc(a)cv.net...
> On 5/7/2010 6:43 AM, Mike Blake-Knox wrote:
>> In article<hric6i$pia$1(a)news.eternal-september.org>, Tim Conway wrote:
>>> Wow! That's fascinating.
>>
>> We received an Earth Day mailing from Sam's Club. It had a $6000 grid
>> tied solar panel system.
>>
>> Mike
>>
>
> Hmm.. Well, in April last year, the general cost for a grid-tied solar
> panel system was $8000 per kilowatt on the roof. I imagine prices have
> dropped a bit, so that's probably for a 1 kW grid-tied.
>
> I happen to have a south-facing roof, tilted around 25 degrees or
> thereabouts, with no shade, all of which is perfect for this kind of
> system. The calculated SRECs for such a system, with 9 kW up there, was
> around 10 SRECs per year. Or, looking at it another way, about 10 MW-hours
> of energy for 9 kW off the roof.
>
> Therefore, a 1 kW roof system (don't know what they're actually
> advertising)would generate roughly 1.1 MW hours of energy. You'll have to
> find out what the electric rates are in your area to see how much that
> saves you, and you'll need to look at your last 12 months of electricity
> bills to see how many kW-hrs of energy you use per year.
>
> Now, with my system, I've got a couple of big honking boxes attached to
> the inside of the garage wall. What was coming, but wasn't really ready
> yet, were solar panels with inverters built right in, so one would get 220
> VAC (or whatever) directly off the panel, no big box in the garage needed.
>
> However, I imagine Sam's club is also including installation. >That< gets
> interesting and requires somebody who's a licensed electrician, knows what
> they're doing, and probably requires an electrical building permit from
> your local municipality. If they're not including installation.. Well,
> unless you've worked, a lot, with household electrical panels, I'd suggest
> a decent electrician.
>
> With these systems, you need at minimum:
> 1. AC cutoff between the solar panels and the grid, on the outside of the
> house. This is for safety in case the electric company has to work on your
> system. No, you can't lock it.
> 2. AC cutoff between the solar panels and the grid, on the inside of the
> house. Safety again, but you get to turn off the power.
> 3. If you're running DC power to an inverter, one DC cut-off box per input
> to inverter box. Safety again, this time if somebody needs to work on the
> box. (Those panels put out anywhere from 100 to 300 VDC at an amp or so.
> Enough to fry somebody if you're not careful.)
>
> There exist grid-tied systems that also have integral batteries. The idea
> is that any excess power goes into charging the batteries first; when the
> solar is generating less power than the house is using (say, at night)
> then the batteries discharge first, then one takes power from the network.
> The plus side of this is even when the AC power to the house goes out, one
> still has power from the DC side, and one's electric bills get even lower.
> The negative side of this is, well, lots of expensive batteries that have
> to be paid for and don't have extraordinary long-term reliability.
>
> Finally, you'll probably need to contact your local electric company. In
> New Jersey, it's practically a requirement that the usual mechanical
> electrical meter be replaced with an electrical one. In this state, you
> pay retail when the electric comes your way; you get paid wholesale when
> the electric goes their other way, just like every other power generator.
> Without the electronic meter the local power company won't be able to
> figure it out and they'll give you grief.
>
> In my case, the people came down and quoted me the $8k/kW price, did a
> site survey, and figured that 9 kW on the roof would zero out the electric
> bill. When given the OK, they came down a few weeks later with a truck,
> five or six people, and installed the whole thing in three working days. A
> pretty job; the local electrical inspector was wandering around inspecting
> it a couple of weeks later with his jaw dropped, something to behold.

What fraction of your daylight hours is the weather cloudy?




From: Mike Blake-Knox on 9 May 2010 09:25
In article <9XsFn.3705$z%6.890(a)edtnps83>, Sharx35 wrote:
> What fraction of your daylight hours is the weather cloudy?

I made my post not because I was considering one but to illustrate how
widely solar panel systems have become available.

We live in western Georgia and have sufficient pine tree coverage that
I haven't gone any further. I have noticed that the Canadian government
has solar energy tax incentives. If solar energy is practical in
Canada, I'd imagine it would be more so in Georgia.

Mike

From: Sharx35 on 9 May 2010 17:02


"Mike Blake-Knox" <mikebkdontspam(a)knology.net> wrote in message
news:VA.0000025a.14df1783(a)knology.net...
> In article <9XsFn.3705$z%6.890(a)edtnps83>, Sharx35 wrote:
>> What fraction of your daylight hours is the weather cloudy?
>
> I made my post not because I was considering one but to illustrate how
> widely solar panel systems have become available.
>
> We live in western Georgia and have sufficient pine tree coverage that
> I haven't gone any further. I have noticed that the Canadian government
> has solar energy tax incentives. If solar energy is practical in
> Canada, I'd imagine it would be more so in Georgia.
>
> Mike
>

It's NOT practical in Canada unless you don't mind paying a LOT more for
your power, re bottom-line costs. If money isn't an issue, well, yeah, we DO
get sun in Canada...unless you are in the far North where it is dark for
months at a time.

From: Ken on 11 May 2010 20:20
On 5/9/2010 2:50 AM, Sharx35 wrote:
>

> What fraction of your daylight hours is the weather cloudy?
>
As one would expect, it varies all over the place!

The trick is, though, that there's tables for solar irradiation data for
any place one might pick, at least in the U.S.. As I understand it, the
data goes back some 20 years.

So, the way the program works in NJ is they tot up your energy usage in
a year, based strictly on past electric bills. The installer's
engineering people take that, the slant of the roof, the size of the
roof, possible shading things like trees, and that solar irradiation
data for the area and come up with an array and inverter system that
will match the previous year's usage.

Yep, there's been weeks when nor'easters blew through where not much
energy got made. The snowy days seemed like less trouble, though: Even
8" of snow up there melted and slid off rapidly once a little sun got on
those dark panels.

As it happens I'm a bit ahead of the game with 1.5 MW-hr excess energy
generated at the end of a year's time. Next year it might go the other
way, I guess.

Ken B.

First  |  Prev  | 
Pages: 1 2 3
Prev: Lost online payees on year-end operation
Next: Has QD2010 changed how reports get customized?