Is this feasible?

[Don]

I built a stand alone building earlier this year, it is 36' x 24'.
2/3 is garage and 1/3 is my office.
In the office I use a Dell computer, monitor, printer, etc. and a pedestal
fan and a 60 watt incandescent lamp.
The computer and fan run for 16 hours a day and the lamp about 4 hours.
I did all the wiring myself (to code, approved and inspected) and the items
mentioned above are on the same circuit.
Can I set up a small PV system that will adequately supply those items for
the time periods that I mentioned and if so where do I start?

As usual I am interested in an economical (but not cheap junk) as well as
low maintenance configuration.
I have good sun on the roof and the ground behind the building and I am
located in southern Indiana.
Have common sense, am handy and have most common tools so I'd like to
purchase the hardware and do the install myself as well as understand how
the system works and how to maintain it.
I'm sort of a noob but I'm willing to learn.
Also, I'd like the system to be possibly infinitely expandable.
Lastly, our total electric bill for the house and the garage is less than
$100 per month, so I am not particularly looking to save money but rather be
in control of our power.
FWIW, I also have a 3500 watt generator.
Thanks for your input.

 

[George Ghio]

I built a stand alone building earlier this year, it is 36' x 24'.
2/3 is garage and 1/3 is my office.
In the office I use a Dell computer, monitor, printer, etc. and a pedestal
fan and a 60 watt incandescent lamp.
The computer and fan run for 16 hours a day and the lamp about 4 hours.
I did all the wiring myself (to code, approved and inspected) and the items
mentioned above are on the same circuit.
Can I set up a small PV system that will adequately supply those items for
the time periods that I mentioned and if so where do I start?

As usual I am interested in an economical (but not cheap junk) as well as
low maintenance configuration.
I have good sun on the roof and the ground behind the building and I am
located in southern Indiana.
Have common sense, am handy and have most common tools so I'd like to
purchase the hardware and do the install myself as well as understand how
the system works and how to maintain it.
I'm sort of a noob but I'm willing to learn.
Also, I'd like the system to be possibly infinitely expandable.
Lastly, our total electric bill for the house and the garage is less than
$100 per month, so I am not particularly looking to save money but rather be
in control of our power.
FWIW, I also have a 3500 watt generator.
Thanks for your input.

Doable, yes. Several thousand dollars.

First you need to define your loads.

List each item, how many watts it uses, how long it is run for.

Multiply the watts by the hours to get Watt hours.

Add all the items Watt hours to get the total daily load.

Then get a Spread sheet from the net(or I can send you one) and calculate your system size.

 

[Don]

Yes you can.

You should start by measuring (using a kill-a-watt meter or similar) your
actual electric consumption.

I have had different Dell computer based systems vary tremendously in
energy use over that time frame. From as little as 1.2 kWh/day to as much
as 4.5 or even 5.1 kWh/day.

If your usage is high, you may find it worthwhile to replace your Dell
with
a more "green" computer. And you should definitely replace your
incandescent with a CF bulb of about 1/4 the wattage rating.


Are you grid-tied? If so, you can figure your size system based on an
average yearly solar insolation. If not, you should figure on worst-month
scenario. You only said you lived in southern Indiana. For Evanston, the
average yearly insolation is 4.68 ESH (effective sun hours) per day with a
range of 2.83 (Dec) - 5.73 (Aug).



Well, first of all you'll need an infinitely sized plot of land where you
can mount your infinite number of panels. If that is not accessible,
you'll have to figure other methods of support .



Making a rough guess that your fan consumes 30W and your
computer/monitor/etc about 150 watts when working; and that you replace
your 60W incandescent with a 15W CF, your daily consumption will be about
2940 W. Once you factor in the various inefficiencies and losses,
including inverter inefficiencies, you'll probably need panels rated at
about 900 Watts. Depending on how good a deal you can obtain, figure
$4-$5/watt just for the panels. Mounts, wiring, controller will add
another $1,000-$1,500. An inverter

So far as the inverter is concerned, that will depend on whether you have
a
laser printer with a big surge; whether you are grid-tied or not; and
other
factors not discussed here.

If you are not grid-tied, you will need batteries for energy storage.

That information should get you started. Let us know how it goes. And
ask
more questions.
--ron

Great, thanks Ron.
Let me mull this over and I'll repost later this week.
I'm going to order the KillAWatt from amazon tonight.

 

[Don]

"George Ghio"> wrote

Doable, yes. Several thousand dollars.

First you need to define your loads.

List each item, how many watts it uses, how long it is run for.

Multiply the watts by the hours to get Watt hours.

Add all the items Watt hours to get the total daily load.

Then get a Spread sheet from the net(or I can send you one) and calculate
your system size.

Thanks George.
If you could send me that spreadsheet I'd appreciate it.
Send it to: moc.hcabnesniL@noD <reverse>
If you or anyone else has any favorite online sources for the equipment
required to do this I'd appreciate hearing about them.

Oh, one other thing.
My new building has a silver reflective ribbed metal roof (over plywood and
trusses) so will it cause any problems or benefits to a PV system if I
choose to mount it up there?

 

[BIll]

I built a stand alone building earlier this year, it is 36' x 24'.
2/3 is garage and 1/3 is my office.
In the office I use a Dell computer, monitor, printer, etc. and a
pedestal fan and a 60 watt incandescent lamp.

You can reduce that 60watt incandescent to about 14watts by using a Compact
Flourescent bulb instead. If you live in a warm climate this will have the
added benefit of reducing the waste heat in your office. The CFL bulb will
last much longer than the incandescent as well.

Just make sure you properly dispose of any CFL lamps at the end of their
life; they should be recycled so that the mercury in them is re-used
rather than re-entering the environment.