The Survival Podcast Forum

Survivalism & Self Sufficiency Topics => Homesteading and Self Reliant Living => Do It Yourself - Projects, Ideas and How To => Topic started by: courageusmind on January 02, 2018, 03:46:38 AM

Title: New Year's Resolution: My DIY Solar System
Post by: courageusmind on January 02, 2018, 03:46:38 AM
In 2017 I managed to save $5,000 for a solar system I am planning to build myself this year. After reading about all the advantages it brings (https://greentumble.com/solar-energy-pros-and-cons/ (https://greentumble.com/solar-energy-pros-and-cons/)) I am super motivated to join the solar movement. I cannot afford an expensive system yet, so I will start small and expand slowly.

Do you guys have solar panels installed on your house or off-the-grid cabin? I would like to hear some stories and any tips that could come handy.

I am planning to start the solar shopping in the next 2-3 months.
Title: Re: New Year's Resolution: My DIY Solar System
Post by: Alan Georges on January 02, 2018, 08:50:18 PM
CM, maybe the best single article on small off-grid solar around is this article from Backwoods Home: http://www.backwoodshome.com/installing-your-own-small-remote-off-grid-solar-system/ (http://www.backwoodshome.com/installing-your-own-small-remote-off-grid-solar-system/)  It's almost ten years old, so many of the components and prices have changed (largely for the better), but all of the basics are covered there.

The same author has a good article about grounding and general electrical safety with small solar: http://www.backwoodshome.com/solar-system-codes/ (http://www.backwoodshome.com/solar-system-codes/)  In fact, he has a lot of good articles about the topic here: http://www.backwoodshome.com/features/author-index/#Y (http://www.backwoodshome.com/features/author-index/#Y), but those are the main two to read.

Another resource is this podcast episode: http://www.thesurvivalpodcast.com/haynes-on-off-grid-tiny-homes (http://www.thesurvivalpodcast.com/haynes-on-off-grid-tiny-homes), and the book they talk about there.  It's pretty much what I've done, but the book has a lot more detail.

Good luck, and let us know if you have any questions.
Title: Re: New Year's Resolution: My DIY Solar System
Post by: jerseyboy on January 02, 2018, 09:28:25 PM
If possible you want an MPPT charge controller.  This allows for higher voltages and lower currents for the same amount of panels.  Smaller currents require smaller wires.  Higher voltages are achieved by connecting in series.  If a panel has an operating voltage of 20 volts, you can connect 5 in series if your charge controller can handle 100 volts.

Also for batteries, series up to 48 volts nominal into a 48V inverter is good if your charge controller can handle 48 volts.  This also lowers current on the battery/inverter side so you can use smaller wire than the same system running at 12 volts.

Also an MPPT controller can often grow with your system while a basic 12 volt one (PCM) cannot.

Good luck
Jerseyboy
Title: Re: New Year's Resolution: My DIY Solar System
Post by: Carl on January 03, 2018, 06:38:15 AM
Let me know how this works out for you.
Title: Re: New Year's Resolution: My DIY Solar System
Post by: redrider on January 03, 2018, 07:43:57 AM
Wow, Great resources, guys!

This is on my list - don't have as much $$$ saved up as courageousmind does, though. I'll work on the education aspects while I save up the bucks.

Thanks for the info and the links.

Good luck, courageousmind, and tell us how it goes.

rr
Title: Re: New Year's Resolution: My DIY Solar System
Post by: Stwood on January 03, 2018, 12:34:40 PM
I will watch this thread. Our oldest brought us a system last year, enough to run the household.
It's a tied in system. I hope to find the used steel trusses and get them put up as a roof system on the back of my south facing shop.
Use it as a shed cover as well as solar panel holder.
Title: Re: New Year's Resolution: My DIY Solar System
Post by: mountainmoma on January 03, 2018, 01:53:03 PM
a basic charge controller can grow with your system if it is sized to do so, so can an inverter.

To me, you have to decide the likelyhoods of if you will expand or not and what priorities you have. A system like mine is probably in the $8-10k range to buy outright, and I have details on some thread here on the forum. Basically, I bought a very, very good inverter as a priority that could do more than I needed at the time, I originally only had 1/2 the panels connect that it would handle, mine now has 2 charge controllers, one for 1/2 the potential panel watts each, my original charge controller is the inexpensive one, and the second one I have is MPPT. My inverter is a grid connected with batteries. My system is 48V. I also initially had less expensive batteries that stored less and had a shorter lifespan, this was upgraded later when they reached the end of life.

a similar sized ( not the same inverter etc... I have) is this, this kit is battery back up and grid intertie, 48V DC to the panels, MPTT charge controller, etc.... https://realgoods.com/the-cabin-complete-solar-pv-kit    I run my whole house, including well pumps, refrigerator, etc... on this many panels. This is $9,000 and I only looked quickly, but seems that the inverter can take more panels in the future.

I realy recommend the technicians at Real Goods, call them and ask your questions, once you have thought more about it and have the questions narrowed down. They are experienced and good.

They also have very minimal, inexpensive kits like this, at $2,400 But this will supply much more limited power, due to the type of inverter. But, it is a very good system for that application. Could be they could help you come up with an inbetween solution https://realgoods.com/the-weekender-complete-solar-pv-kit?nosto=productpage-nosto-1  This has a 1.5kWh inverter, a MPTT charge controller and is a 24V system with batteries
Title: Re: New Year's Resolution: My DIY Solar System
Post by: Alan Georges on January 04, 2018, 06:01:09 AM
This is on my list - don't have as much $$$ saved up as courageousmind does, though. I'll work on the education aspects while I save up the bucks.
RR, you can start much smaller too, if all you're trying to do is have backup power to keep a few lights, a cell phone, and a radio running.  The book by Chris Haynes has three example systems in the back.  The smallest could probably be built for around $200.
Title: Re: New Year's Resolution: My DIY Solar System
Post by: redrider on January 04, 2018, 07:34:47 AM
Thank you, Alan. I hope I can do something soon. It's my budget of time too, in addition to money.

I actually have a solar panel that I got a few years ago but I need to educate myself on the other components (controllers, batteries, wiring, etc.) before I'll have a system. I need to learn a lot.

I'll be interested in following courageousmind's project.

rr
Title: Re: New Year's Resolution: My DIY Solar System
Post by: courageusmind on January 11, 2018, 02:43:48 AM
CM, maybe the best single article on small off-grid solar around is this article from Backwoods Home: http://www.backwoodshome.com/installing-your-own-small-remote-off-grid-solar-system/ (http://www.backwoodshome.com/installing-your-own-small-remote-off-grid-solar-system/)  It's almost ten years old, so many of the components and prices have changed (largely for the better), but all of the basics are covered there.

The same author has a good article about grounding and general electrical safety with small solar: http://www.backwoodshome.com/solar-system-codes/ (http://www.backwoodshome.com/solar-system-codes/)  In fact, he has a lot of good articles about the topic here: http://www.backwoodshome.com/features/author-index/#Y (http://www.backwoodshome.com/features/author-index/#Y), but those are the main two to read.

Another resource is this podcast episode: http://www.thesurvivalpodcast.com/haynes-on-off-grid-tiny-homes (http://www.thesurvivalpodcast.com/haynes-on-off-grid-tiny-homes), and the book they talk about there.  It's pretty much what I've done, but the book has a lot more detail.

Good luck, and let us know if you have any questions.

That's a lot of awesome material right there. All I needed! I better start digging  :) Thanks a lot!
Title: Re: New Year's Resolution: My DIY Solar System
Post by: courageusmind on January 11, 2018, 02:51:28 AM
If possible you want an MPPT charge controller.  This allows for higher voltages and lower currents for the same amount of panels.  Smaller currents require smaller wires.  Higher voltages are achieved by connecting in series.  If a panel has an operating voltage of 20 volts, you can connect 5 in series if your charge controller can handle 100 volts.

Also for batteries, series up to 48 volts nominal into a 48V inverter is good if your charge controller can handle 48 volts.  This also lowers current on the battery/inverter side so you can use smaller wire than the same system running at 12 volts.

Also an MPPT controller can often grow with your system while a basic 12 volt one (PCM) cannot.

Good luck
Jerseyboy

I'll definitely go with a MPPT charge controller. Thanks