Posted by *Steve Spence* on September 10, 2005, 9:15 pm

Drew Cutter wrote:

*> Steve how do i find out how much the central a/c consume in power. I'm *

*> in Ohio. If you have a better solution ,let me know. Thank.*

*> *

Your documentation should give a yearly kWh average, for basic

calculations. A clamp on ammeter would give current draw for a given

point in time. An hour meter would give you run times per day, but you'd

have to calculate fan and compressor current draw and elapsed times

separately.

compressor current draw (amps) * volts = watts

watts * daily hours = compressor watt-hours

fan current draw (amps) * volts = watts

watts * daily hours = fan watt-hours

compressor watt-hours + fan watt-hours = total watt hours daily

It's usually not cost effective.

--

Steve Spence

Dir., Green Trust, http://www.green-trust.org

Contributing Editor, http://www.off-grid.net

http://www.rebelwolf.com/essn.html

Posted by *Drew Cutter* on September 10, 2005, 9:49 pm

I'm guessing from paul posting , that the best i can do is reduce my

electric bill.

Steve Spence wrote:

*> Drew Cutter wrote:*

*> *

*>> Steve how do i find out how much the central a/c consume in power. I'm *

*>> in Ohio. If you have a better solution ,let me know. Thank.*

*>>*

*> Your documentation should give a yearly kWh average, for basic *

*> calculations. A clamp on ammeter would give current draw for a given *

*> point in time. An hour meter would give you run times per day, but you'd *

*> have to calculate fan and compressor current draw and elapsed times *

*> separately.*

*> *

*> compressor current draw (amps) * volts = watts*

*> watts * daily hours = compressor watt-hours*

*> *

*> fan current draw (amps) * volts = watts*

*> watts * daily hours = fan watt-hours*

*> *

*> compressor watt-hours + fan watt-hours = total watt hours daily*

*> *

*> It's usually not cost effective.*

*> *

Posted by *Drew Cutter* on September 10, 2005, 9:53 pm

From the web page Paul. Only one town near me gives net meter of 25

kw. So what size solar would i need ? I will have to check my town

requirements.

Drew Cutter wrote:

*> I'm guessing from paul posting , that the best i can do is reduce my *

*> electric bill.*

*> *

*> Steve Spence wrote:*

*> *

*>> Drew Cutter wrote:*

*>>*

*>>> Steve how do i find out how much the central a/c consume in power. *

*>>> I'm in Ohio. If you have a better solution ,let me know. Thank.*

*>>>*

*>> Your documentation should give a yearly kWh average, for basic *

*>> calculations. A clamp on ammeter would give current draw for a given *

*>> point in time. An hour meter would give you run times per day, but *

*>> you'd have to calculate fan and compressor current draw and elapsed *

*>> times separately.*

*>>*

*>> compressor current draw (amps) * volts = watts*

*>> watts * daily hours = compressor watt-hours*

*>>*

*>> fan current draw (amps) * volts = watts*

*>> watts * daily hours = fan watt-hours*

*>>*

*>> compressor watt-hours + fan watt-hours = total watt hours daily*

*>>*

*>> It's usually not cost effective.*

*>>*

Posted by *Paul* on September 10, 2005, 10:43 pm

I would say that it is always best to check out any regulations,

requirements

and rebates before deciding. In California they will pay $-3 a watt for

your

PV system and Netmeter at the rate you pay for electricity. If you are

producing

electric at high noon on a summer week day you could get even more with

time of day Netmetering. Check you local listings...your milage may vary :)

*> From the web page Paul. Only one town near me gives net meter of 25 kw. *

*> So what size solar would i need ? I will have to check my town *

*> requirements.*

*> Drew Cutter wrote:*

*>> I'm guessing from paul posting , that the best i can do is reduce my *

*>> electric bill.*

*>>*

*>> Steve Spence wrote:*

*>>*

*>>> Drew Cutter wrote:*

*>>>*

*>>>> Steve how do i find out how much the central a/c consume in power. I'm *

*>>>> in Ohio. If you have a better solution ,let me know. Thank.*

*>>>>*

*>>> Your documentation should give a yearly kWh average, for basic *

*>>> calculations. A clamp on ammeter would give current draw for a given *

*>>> point in time. An hour meter would give you run times per day, but you'd *

*>>> have to calculate fan and compressor current draw and elapsed times *

*>>> separately.*

*>>>*

*>>> compressor current draw (amps) * volts = watts*

*>>> watts * daily hours = compressor watt-hours*

*>>>*

*>>> fan current draw (amps) * volts = watts*

*>>> watts * daily hours = fan watt-hours*

*>>>*

*>>> compressor watt-hours + fan watt-hours = total watt hours daily*

*>>>*

*>>> It's usually not cost effective.*

*>>> *

Posted by *Ed Earl Ross* on September 11, 2005, 1:51 am

Steve Spence wrote:

*> Drew Cutter wrote:*

*> *

*>> Would a solar panel work for running a central a/c for the house ?*

*> *

*> *

*>>>*

*> A solar thermal array could drive a absorption AC unit. It would take a *

*> bunch of PV panels to drive a electric compressor unit. If a central a/c *

*> unit consumes 3500 watts for 8 hours per day, it uses 28 kWh's / day. In *

*> sunny California, you might need 5kw of PV panels to run it, at a cost *

*> of over $0k just for the pv panels. More than double that for NY.*

*> *

You can save energy by setting a warmer temperature.

There are split or ductless room air conditioners that are nearly

as efficient as central air, but allow you to air condition room by

room. Conditioning only rooms you use, may save on electricity, and

the cost is much less than PV. Conventional window units are much

less efficient, but cost less too.

If you live in a humid climate, you may be able to save on

electricity by installing an adsorption dehumidifier; though, I

don't know if any are made for home use. Lower humidity allows you

to be comfortable at a warmer temperature.

--

Humbly--Ed

"If the man doesn't believe as we do,

we say he is a crank, and that settles it.

I mean, it does nowadays, because now we

can't burn him." (Mark Twain)

> Steve how do i find out how much the central a/c consume in power. I'm> in Ohio. If you have a better solution ,let me know. Thank.>