Our Solar Panels Are Back Online (after a 2-3 year reprieve)
After collecting dust for a few years through our transition from last house to current house, we have our solar panels once again producing energy for us! I installed the solar panels on our house roof this last summer while re-roofing. Over the last month or so, we have once again started utilizing the power they provide.
Future plans include a significant expansion of solar panels, on the south side of either our garage or barn roof that would supply 230/120VAC power through an inverter. While we do have a 120VAC inverter on-site, I try to avoid using it as it wastes power just sitting there connected to the system, even if no connected devices are consuming any power. My system is just not large enough to handle that much waste. For sake of efficiency, at least for the time being, we are consuming all the power generated by the system as 12VDC.
We have two 12VDC 150Ah AGM marine batteries used to store power for use when the sun is not shining. Those are fed to a small breaker box that is then fed out to various systems in the house.
Now you may wonder, what could we do with a 12VDC power source in the house? Turns out, a lot!
For starters, we save money by running the well less through the use of a compositing toilet. Turns out, our compositing toilet's fan is 12VDC and can be powered straight off of our solar charged batteries.
How about lighting? All of our kitchen under counter lighting, closet lighting, desk lighting, and other various areas of the house are lit with 12VDC LED strip lighting. They are extremely cheap and extremely bright! They come in 16.5ft lengths with can be easily cut and soldered to any length.
(Ignore our beautiful back-splash, just waiting for it to warm up outside so I can run the tile saw)
We implemented 12VDC motion sensors in two rooms that auto turn the lights on (and more importantly, off).
In our central vacuum closet, I installed a magnetic switch that will be mounted to the future door, so when the door opens, the lights turn on (think Maytag refrigerator commercials from the early 2000's). When the door closes, the lights turn off. I will be installing the same switches in our coat closet that I started building last weekend, along with installing them inside all of our kitchen cabinets.
We installed 12VDC USB outlets throughout the house. These outlets provide (5VDC) USB ports that allow you to power any USB devices. For example, we now charge our phones, tablet, kindle, cycling cameras, and bike computers using solar generated energy. We even recharge our AA and AAA batteries using solar energy.
(my new desk/work area is lit with solar power LEDs)
How about our Ethernet switch? Yep, turns out that will accept 12VDC and will be getting migrated in short time too!
We also power a bluetooth receiver for our home sound system from solar powered USB. I even spec'ed and purchased a sound amplifier for our home sound system that will be powered off of 12VDC.
Spring power plans include adding two panels and a battery to the garage and three panels and two batteries to the barn. I will be installing inexpensive 12VDC LED lighting throughout the barn and garage. I will also be installing a small 12VDC stock tank heater I have waiting patiently for me in the garage, before next winter hits.
As we are slowly transitioning to an off-grid lifestyle, I think these simple projects show that living off-grid does not mean saying goodbye to modern conveniences.
When running the numbers, out solar system will provide a ROI after about 10 years. It also brings a piece of mind in the case of a power outage and an overall warm-and-fuzzy feel when thinking about all of these devices being powered in a sustainable manner with no costly inputs after the initial investment.
Are you currently converting solar energy into electricity? Are you running off 12VDC? What kind of things are you powering?
-Jeremy
Blog: http://mnhomesteader.com/blog/
Facebook: https://www.facebook.com/mnhomesteader
I see you got 2 panels. Can you tell how much power it generates in KiloWatts per hour?
Using sunshine numbers for my region, my panels generate about 22kWh/month which is currently, in my household, equal to about a days worth of electric usage through our power company.
22kWh? That is enough to power up 15-20 heavy miners or 4000 light bulbs. Average family usage at peak is 10 kwh, which means that 22kwh is enough for two houses. Are you sure your solar panels are that strong?
Solar Panel Wattage x Solar Radiation Coefficient for Minneapolis = 0.160 kW x 4.54 =0.7264kWh -> 0.7264kWh x 30.5days = 22.155kWh/month
From my power utility:
My household average power consumption/day=27kWh (in the winter)
Our neighborhood average power consumption/day=73kWh (in the winter)
Further reference: https://answers.energysage.com/question/102/if-a-solar-panel-is-rated-at-300w-how-much-power-will-it-produce/
Also, not sure where you found 10kWh as the average daily family usage, you may want to reference: https://www.eia.gov/tools/faqs/faq.php?id=97&t=3
kWh means per hour, if your daily usage is 27 kilo watts thats of course normal.
What I meant is that at peaks one family can use up tp 10Kw at once, that is why the power matters. Let's say you want to use the oven, iron, boiler, microwave, dishwasher and AC simultaneously.
27kW/day means 1.125kW average hourly usage.
Power matters, for sure. Our system would not simultaneously run our fridge, stove, and well, for instance. I have not invested into it enough for it to do that, nor have I designed it to do such (yet). We are speaking different units. I was referencing the kWh my panels generate in a single month, a measurement of power over time. You are referencing kW, a measurement of power at a given instance in time.
I was not aware that you could install USB outlets, how cool is that and a huge life saver when you can't find the block to plug in. Thanks for the education.
With so many USB devices out there, USB outlets are so useful! Thanks for stopping!
Nice post you can do a lot with 12 volt DC power.
follow and upvote
Thanks! Looks like we have a lot in common while looking over your blog. Following you too!
Thanks
Im impressed. You are doing well with the 12V lifestyle and have inspired me to finish my own wiring and write my own post.
Here's to hoping your install goes well!! It is pretty satisfying when you can produce your own energy off your own homestead!
Nice work. I admire people like you who are always looking for alternatives. You write your system will payback after 10 years but you already had these solar panels for couple years, right? Was it costly to transfer them from your previous house?
Thank you! I bought these panels back in 2010, however, there were a few years in there that they were not in use due to the move and waiting on getting around to re-roof our current house so I had a place to install them. As it was just two panels and I only moved 3 miles away from our last house, it did not cost anything to remove them, just a little time :)
Sounds like we had similar thinking about running a lot of things straight off of 12v DC power. We have 12v DC strip lighting throughout our tiny house and they are very efficient.
We also came to the same conclusions about inverters. They tend to draw a fair bit of power idling.
Right on! Those 12VDC LED light strips are worth every penny they charge for them. They open up so many options! We have plans to built two small off-grid "grain bin houses" on our property with the same idea, everything will be 12VDC. It was brought to my attention that I may have to put in an inverter in the bathrooms for the female guests though.
For hair dryers or something?
Something like that!
This is great! I am living off the grid as well on a boat. I just put up some posts on how to install solar and battery types. What made you choose AGM?
I came across a really good deal on two AGMs a few years ago through a friend. If the price on lithium-ion would come down a bit, I would start buying them, but currently the AGMs seem like the best balance between price/capacity. This summer I will be on the market for some batteries for my outbuildings. What kind of batteries did you go with?