AC electric only Tiny Home solar system for a family of five.

[23teamnewman24]

My family of five is packing and planning for the shell build on a 32' x 8.5' gooseneck trailer built Tiny Home in April 2021. We will be traveling to find a "home" because we have only lived in two cities, and have no idea where to buy land with elbow room at yet. While we travel we will need homeschooling/work from home computers, and washing power. Water is a big issue for us right now but I want to make sure we got the solar on its way. We fond a point of entry water heater that only uses 3kw for the kitchen sink, and one for the shower. (We are connecting a ozone filter for the water for the dishwasher and washer/dryer combo to reduce the need for hot water/soap). So, so far, we are on a good track on minimizing power and having the needs for a large family sorted. We, have a pump and a 11 step filtration set up for the grey water recycling, mini split ac, the electric toilet incinerator, the washer/dryer combo, the fridge, the oven, the two burner cooktop, the tv/laptops and then outlets/lights. My husband has been able to better understand solar bc of Will Prowse however, I haven't seen any videos of expanded systems for large family uses. If you can direct me to that lmk. I have been slamming keys and trying to calculate, and so far I believe we will need a 9 kw system capable of producing 1,000 kwh a month with the specific AC items I have which is about 23; 400w panels. Yet, I haven't decided on the roof style for the shell because I just can not find the best solar plan that actually !FITS! I calculated once I could fit 15 upon sft and another time only 9 when I drew it to size in scale....but nontheless I will need aprox. 23 and thats using a 400kw panel So I have more solar feet needed than I do house available. So far we are almost looking at a $18k investment, but odds are push it to $20k because we will have to hindge the solar from the roof side to push up/out. You are all brilliant I have seen, I am sure there are suggestions I could use to help the creative wheels.

Thanks!

 

[snoobler]

Welcome.

Consider if you're taking the conservative approach.

AVERAGE household in America uses 30kWh/day. You're on pace to use more than this in a tiny home.

1000kWh/month = 33.3kWh/day

Accounting for inefficiency in electric conversion and other losses:

33.3kWh/day / 0.85 = 39.2kWh/day

You'll need 39.2kWh usable capacity of batteries. For lead acid, you need 78.4kWh (50% usable). For LFP, you need 49kWh (80% usable).

Depending on your location, panel orientation and tilt, as long as you get at least 4 hours of solar irradiance per day (no shading of any kind all day long), your 9.2kW array should suffice.

Fitting all that on your trailer home is impossible. I have a 40'x8' shipping container, and I can barely fit 6kW on it.

Plan for ground mounts.

SWAGs:
About $6000 for a DIY LFP battery.
About $4500 for the array.
$1500 in SCC
$5000 in inverters
$1000 in cool stuff (integration, monitoring etc.).
? in misc. that you just never think of, and the nickels and dimes that add up.

$18-20K is probably pretty close.

 

[Craig]

I think it can be done for around 18k.

i would consider making a rack system for the solar panels that can slide out so that you can double or triple your roof space and even have a small awning of panels to boot. The one thingthat worries me is if the panels are flat you will have seriously diminished capacity in the winter. I in no way want to be discouraging just thinking of an issue that may need to be addressed.

I also think you may could save some money by trying to figure out ways to save energy as well which saves on everything else involved as well as needing potentially less panels for your small roof.

 

[HaldorEE]

Propane or diesel is a much less expensive way to heat things than solar electric. Just saying.