NEW Guy in Northern Arizona looking for info

Re: NEW Guy in Northern Arizona looking for info

Welcome to the forum Ray!

Sevn wrote: »

Hello, My name is Ray I decided to join a forum to pick people's brains on planning a solar power system. I just bought a house on 5 acres in Apache County, AZ close to Concho.

Lots of land and sun--Check--Good for solar.

I'd like to make a system that can be improved upon and expanded in the future. In time I'd like to have a 20kw+ system that can be used for welding if possible.

In general, solar power does not expand well. It is like buying a VW bug and slowly tricking out to be an 18 wheel semi hauling 40-80 tons. Not very many original parts are going to be in the final build.

Solar panels and Solar Charge Controllers (MPPT types from Outback, Midnite, and similar) can be moved/installed on upgraded systems. In general, battery banks, AC inverters and such--Not really.

I have obtained some items from bartering the last few years. I have three 50w 2ftsq solar panels and 10 6v 232amh deep cycle marine batteries. I'd like to start off with something but might wait until more panels and an inverter controller is selected this depends on money barter and life.

3x50 Watt panels times 6 hours of high summer sun:

• 150 Watts of panels * 0.52 system efficiency * 6 hours of summer sun = 468 Watt*Hours of "useful" solar energy per day

So, what is 468 WH of energy look like? Can run a single energy efficient laptop computer for 10-12 hours per day.

Can run an efficient full size refrigerator for about 8 hours per day.

Can run 4x 100 light bulbs for around 1 hour per night.

Look at your power bill, if you are an "average" user of electrical power, you use somewhere around 1,000 kWH per month (or if you have lots of Air Conditioning usage, could be as much as 3,000 kWH per month).

• 1,000 kWH/30 days per month = 33.3 kWH per day = 33,300 Watt*Hours per day

How much is 468 WH?

• 33,300 WH per day average home / 468 WH (from 150 Watt system) = ~71.2

Your utility power could easily be somewhere around 70x the amount of solar panels you have today... Pretty much "rounding error" in your power usage.

My house is on local metered water and power so my well and solar projects might not be started for sometime but this can give me time to design a large enough system to provide all power needs.

In general, off grid power is not going to save money for you unless your power costs spike to $0.50 to $1.00+ per kWH. (in California, we have some rates that are in the ~$0.50 per kWH for heavy power users today).

So--To save money, there is Grid Tied solar power.... Basically a bunch of solar panels and a GT (grid tie) AC inverter that pumps energy backwards into the utility's power system. And turns your power meter backwards. These can save money for many people--But this depends on how much you pay for power, how much the utility will pay you for power you generate, and future political winds (GT solar is getting push-back from utilities, including in Arizona).

Any ideas or comments are appreciated. Questions I have are; can the grid be used as a back up or to charge batteries while system is in use? I imagine a system where you draw from your battery bank which is being charged by the charge controller and when the suns down and batteries are low the grid power . Is this doable? Would multi chargers or inverters be better??? Also can wind be integrated into a solar system or separate system??

You are in an age where almost anything you can think of with solar power, it can be done with pretty much off the self equipment.

However, as soon as you have a large system with battery banks and large AC inverters+charge controllers--You are talking about a relatively expensive installation ($20,000 to >$100,000 to power an "average" North American home today). Plus you need to replace batteries every ~5-10+ years, and new inverters+charge controllers every ~10+ years.

So--First think, do not get any more equipment just yet. Figure out what you want to do and make some paper designs and costing plans.

My recommendation:

1. Review your energy usage around the home. If you never have tried much in the way of conservation/have an older home, it is very possible to cut your energy bill by ~1/2. And, in general, it is much cheaper to conserve energy than it is to generate electricity.
2. If you are still interested in solar--Build a smaller system that will generate around 1 - 3.3 kWH per day for ~9 months of the year. A 1 kWH per day system will light a cabin, run a laptop+radio, small water pump. A 3.3 kWH per day system will also run a Refrigerator+Clothes washer+Well pump in a very efficient single family home with "near normal" electrical existence (using propane, natural gas, solar thermal, etc. for heating/cooking/hot water).
3. If you want backup power--Get a generator for your home with your fuel of choice (propane is nice to store, gasoline and diesel are easier to get sometimes). For 2 weeks or less of power outages a year, a generator is cheaper and requires less maintenance vs solar power
4. More backup--Build out a battery bank + AC inverter + AC battery charger. Will allow you to run overnight to a couple of days without firing up the genset. Very nice for quiet evenings/nights, and run the backup genset during day time to recharge battery bank and power heavier electric loads
5. Add solar panels to backup batter bank... Less generator run time.
6. If you are still interested in Wind Power, now you have solar+genset+battery bank, you can figure out if wind will help you or not. In general, wind generators will only generate "useful" power on a 60 foot+ tall tower on a miserably windy day. If your place has few windy day, a wind generator is not going to help much (if at all). Wind turbines are not too expensive, the towers, concrete base, wiring, electronics, and crane/lift truck to service the turbine all cost way more than the turbine itself.

Anyway... A few suggestions. First thing is to know your power. You can get whole house monitors, per appliance monitors, etc. to give you some numbers. Check your monthly kWH usage on your power bill.

If you want some other ideas--This thread is a good start:

http://forum.solar-electric.com/showthread.php?5556-Working-Thread-for-Solar-Beginner-Post-FAQ

-bill