Monday, June 16, 2014

A Tough Math Day

Solar power racking is underway!

It's something we both avoided speaking about and dreaded starting- although, in the grand scheme- I have no idea why! Saturday, Dan was able to grab a few hours working for his Dad so he took it.  He's still struggling to find something part time that will work with school. If anyone in the Rhode Island area has any suggestions, let us know! While he was off earning some keep, I tackled a list of errands. Neither of us returned home until about 3pm, at which point, we called it a day. Well sort of- we grabbed showers and free movie passes at his parents so we could head out and see How To Train Your Dragon 2. Yes. That was my requested movie. I loved it almost as much as the first!

Anyways, after a day doing other things, it meant Sunday was a work day, noooo compromises. We hope to move the tiny house next weekend, so we need to get crackin!

We researched a few different ways to mount solar panels, and finally decided to go with the ideas shown in this youtube video. We made a few of our own modifications, but the over all concept is similar. 

We have 8 solar panels to build for, so we plan to make four smaller versions of this which will hold two panels each. We plan to put two racks right next to one another to make a 13 foot row of four panels. We will have two rows. That's a lot of sun power right there! I keep seeing all of these tiny houses with just one or two panels sitting out front and I wonder how the heck they manage with that. This is our home full time, and of all things to skimp on, solar power wasn't one of them. I work from home some days, and I KNOW there will be days in the summer when we thank our stars that we can run an A/C and days in the fall when we are happy to be able to plug in the small eco-heater- because the main stove would be too much. 

It's still a very modest system. Here is what our load calculator chart looked like- and it gives you an idea of what we can run.

Appliance Load/ Name On At Same Time Quantity AC Watts Hours on Per Day Watt Hrs/ Day
Cooler Y 1 70 8 560
Great Rm Lights Y 1 50 6 300
Kitchen Light Y 1 10 4 40
Blender/Juicer - 1 300 0.1 30
Sewing Machine - 1 100 0.1 10
Table Fan Y 1 25 7 175
Computer (Laptop) Y 1 50 6 300
Window Fan Y 1 40 6 240
Clock Radio Y 1 1 24 24
A/C (or heater in winter) - 1 600 4 2400

So our total system is 4079 Watt-Hours Per Day. Without the A/C option we would be down to just 1679 Watt-Hours per day. That would be nice on the wallet, but I've sat through more than one scorching day with no A/C and I'm not about to make us tough it out in that little box on wheels!  This chart comes right from the AltE website. They have a lot of great calculators that make it much easier to understand what you are calculating, and provide a lot of the basic appliance power loads for you!

The board at the bottom of this pic
is the where the panel goes.
Anyways- back to the racking. So we went out early and got our rough estimate of needed supplies. Then the mind-melting math came in. When I say mind-melting, please don't take that as an indication that it was truly hard- it was just one of those days when we both were suffering from chronic brain farts and could not process basic geometry. I lost count of how many times we talked out our moves and our cuts and our measures, only to pause right before beginning and say, "Wait....go over that again?" 

On our first run through, we made the cuts "upside-down" the first go round, meaning, if we had put the rack up, the solar panel would be at the exact opposite angle of what we needed. After doing the math for our latitude, we found that 35 degrees would be optimal. A triangle always adds up to 180, and we had our 35 and 90 degrees, so the last angle was 55. What we got mixed up on (among many other things that day) was which corner needed to be 35- the top corner or the bottom one?

I'll cut to the chase and tell you- it's the top. It may have taken us a few hours, but we finally got all of our cuts, angles, and measurements right. Our first racking post was complete. We spent another hour or so making cuts in an assembly line manner. By the end of Sunday, we had completed two of the eight posts we will need.

We didn't get it all done, but man does it feel good to have sailed over the hurdle of just-getting-it-started. We have about 40% of the wood cut. Throughout evenings this week we will complete all the posts and hopefully head over to the farm to mount them in the ground. 

Thanks for reading!
Like Us On Facebook 

Yep! It fits! Woooh!


  1. What sort of batteries will y'all be using? And did y'all wire the tiny house for 12V or are y'all using an inverter? I am still struggling with understanding solar power and how it would best work for us.

    1. Hi there, Drew! We decided to go with AGM batteries. There are flooded batteries and sealed batteries, each with their pros and cons. Flooded batteries are much cheaper, but require maintenance (adding more liquid) specific storing instructions, etc. Sealed batteries are more expensive, but just as they are called- they are sealed. So there is less maintenance/hassle...less worry about off gassing, and they generally hold up better in cold temperatures. The specific type of battery we chose also does well with deep discharges...meaning using up just about all the power that is stored. We went with AC power because we already have several items that require AC power such as our computers and other gadgets. We went with a pure sine wave inverter too- its supposed to be more efficient. We wired the house as you would any traditional house using 12 gauge (or maybe it was 14?) house wire. DC is definitly the way to go for more efficiency and a more cost effective system, but you have to find all DC appliances as well- which can be difficult and more expensive some times. I highly recommend checking out - even if you don't plan to purchase from them, they have a substantial library, reference section, online webinars, video tutorials- it's quite a find I think! Good luck to you if you decide to go with sun power in the future! :)

  2. Get daily ideas and methods for earning $1,000s per day FROM HOME totally FREE.

  3. There's a chance you qualify for a new government solar program.
    Find out if you're eligble now!

  4. Good read and Great article. I want say that this article is very nice and very informative article.I will make sure to be reading your blog more. 

  5. Cheers for this excellent. I was wondering if you were thining of writing similar posts to this one. .Keep up the great articles! Zonnepanelen installateur