How do I size my off grid system?

[armourereric]

Here is my scenario:

I am interested in a lease/option on a nearby 40 acre farm that has been idle for many years. The property has been cut from the pole, the hassle of a reconnect, plus the factor of having the most expensive electricity in the US makes me option for an off grid system.

It is a 1200 sq ft home, but I will have many aggravating factors: 2 Poultry brooders running 600 watts 24/7. Plus I have a workshop with a 5500 watt/240v electric heating oven that I use to make medieval armour from specialty metals, I use the oven once/twice a month for less than 4 hours.

This is a high wind area with 3000 industrial wind towers planned, hence I would like the option of adding a windmill at some point. I am near the Mexican border with ample sunlight. I am also very skilled at constructing and designing stuff. I would like to build my own system from scratch. I want to place the solar array on a moveable trailer.

How can I determine the size of the system I need?

[Sunking]

Just read the Stickies starting with this one in the Off-Grid Section.

Once you figure out how much it is going to cost, you will be calling the Power Company real quick to reconnect you.

[Mike90250]

Sorry, but with your loads, I'd suggest the Grid re-connect. To do it with solar, generators and batteries, would still be more expensive.
The other alternative you alluded to - Wind, is not recommended, unless you have really good mechanical skills to maintain high speed rotating machinery that can throw blades half a mile, and gear to get you to the turbine, or lower the turbine to you

For wind info, look up Scoraig wind, Hugh Piggott for the best DIY gear.

[russ]

For wind also see http://www.solacity.com/SmallWindTruth.htm

If you don't have a tall tower - forget it
If you don't like to tinker - forget it
If you don't want to make a large initial outlay forget it
If you are thinking of one of the residential small turbines - forget it

[SunEagle]

Here is my scenario:

I am interested in a lease/option on a nearby 40 acre farm that has been idle for many years. The property has been cut from the pole, the hassle of a reconnect, plus the factor of having the most expensive electricity in the US makes me option for an off grid system.

It is a 1200 sq ft home, but I will have many aggravating factors: 2 Poultry brooders running 600 watts 24/7. Plus I have a workshop with a 5500 watt/240v electric heating oven that I use to make medieval armour from specialty metals, I use the oven once/twice a month for less than 4 hours.

This is a high wind area with 3000 industrial wind towers planned, hence I would like the option of adding a windmill at some point. I am near the Mexican border with ample sunlight. I am also very skilled at constructing and designing stuff. I would like to build my own system from scratch. I want to place the solar array on a moveable trailer.

How can I determine the size of the system I need?

For just those 2 brooders you daily electrical usage is around 29kWh. Add a few more small loads for lighting and tools the usage can easily go above 35kwh a day. You would need about 10,000 watts of solar panels (which will not be easily moved via trailer) and a very big battery system. After you add racking, charge controllers, inverters, wiring and fuses a quick estimate for that system is > $80k and you will need to replace the battery system in 5 years for another $40k.

Even if your electricity costs $0.55/kWh like they do in Hawaii it would be cheaper to get connected to the grid.

If you want to go solar then install a grid tie system but forget the batteries and don't even think about getting a wind turbine due to the high maintenance (labor & material) to keep it working.

[armourereric]

Thank you for the comments thus far. From what I understand electricity is currently 37 cents/KWH. One big factor is that in order to goon grid, SDG&E wants nearly $10000 in fees to reconnect, SD county wants the whole electrical system of the home replaced for another who knows how many 1000's. As it turns out I will not need the system for many months yet so I will take this time to educate and experiment. I will slowly build an off grid system for my 500 SQFT trailer. As for some of the above inquiries: I LOVE to tinker, I may attempt my own wind tower, it would be over 2200 feet away from the nearest neighbor (one neighbor has a vertical wind turbine made from the former stanchion of an old Union 76 rotating gas station sign with modification, he is off grid.) and it would not be one of those little residential jobs. I will also investigate a peaker gas generator for when I do go across the street to my new farm.

A common neighbor to both parcels has just put in a massive system (at least to me), I have invited him over for dinner later this week to discuss. Here is his array on Google.

http://goo.gl/maps/PuJ8J

The 40 acres I am buying is immediately to the south, terrain across the property varies by a good400 feet in elevational difference.

[armourereric]

My first step will be to get an electric meter off of ebay and meter my trailer outlet to determine usage.