My Tiny Motor House
My minimalist quest to live off grid in the desert in a modified 1977 Dodge motor home rebuilt from mostly recycled, and re-purposed stuff. It's a purposeful lifestyle of survival to help prepare me for a possible mission to Mars in 2034... or something like that.
Saturday, November 4, 2017
Random Bathroom Modifications
New Windows and Painting the Loft
No more leaky RV windows!
I almost forgot how totally warped the floor of the loft is until I moved my bed, boarded up the trap door cab access thingy (I have no idea why that was even a thing in these old RVs) and painted it.
Saturday, August 26, 2017
Off-grid Living is More Energy Efficient!
Just look at the above graph. People complain about how expensive it is to set up a solar power system (photovoltaic system), but in my last article I showed you how to set up a quality off-grid system using parts ordered right to your door from Amazon.com for about $2.2k. Hold on, look at the graph again! The average home in the United States in 2009 spent $2,024 in one year. So basically:
You can set up a solar power system that will power your home flawlessly for 5 years (until you may have to replace the batteries) and another 10 years (until you may need to replace the panels) for the cost of powering your home from the grid in one year!
I'm sorry, but it sounds like the person who said solar power was expensive was the idiot here....
In the United States the average household uses 901 kWh of energy per month or about 30 kWh per day (eia.gov).
Since I updated my electrical system at the beginning of this summer I've been keeping track of my energy consumption. Over the past three months I have used 128 kWh of energy. That's only about 1.4 kWh per day! Keep in mind it wasn't just me living here during the summer. It was me and my two kids (with my kids playing a significant amount of Minecraft). Just to give you some perspective:
The energy consumed by the average american home could power 21 tiny homes like mine!
or
The energy wasted by a conventional electric water heater could power 14 tiny homes like mine!
Now I should keep in mind that I haven't just been using electricity. I have used about 3 gallons of liquid propane (maybe less) for cooking and heating water, and about 2 gallons of gasoline (to run my generator for power tools), but that's barely anything over the course of 3 months! In the winter I used quite a bit more propane for heating (like 20 gallons for the entire winter), but I got a new propane furnace for this coming winter and I'm making a new wood stove. So, only time will tell for this coming winter.
The way I'm living is about 20 times more energy efficient than the average American household! Why do we live in such a wasteful society? Imagine if we could downscale our consumption we could easily reduce energy consumption and carbon emissions to a 20th of what they are today.
The interesting thing is I'm not really having to make any conscious sacrifices in energy consumption as far as my daily life goes. I still use my laptop, phone and other devices just as much as I did when I lived in an apartment--maybe even more. The big difference is really not in the lifestyle change, but in eliminating the appliances that waste energy and replacing them with more energy efficient appliances.
How to Setup a Quality Solar Power System for Off-grid Living on a Budged
I know I've written on this before, but I decided it was time to make a detailed step-by-step guild to setting up your own off-grid solar power system.
In this post I will show you:
- Everything you need to buy
- Exactly how everything needs to be wired
- Tips on building your system
- How to make simple rotating solar panel stands
What You Will Need:
I've found that one of the hardest parts about setting up an off-grid photovoltaic system is that you either have to hire a professional to set them up for you or you have to spend weeks researching what components will work well together. Well, I've been living completely off the grid for over a year now and through a lot of research and first-hand experience I've found what works well and is hassle free.I've done the hard part for you and setup an Amazon shopping list where you can just directly add everything you need to your shopping cart (pay attention to the quantity as it doesn't automatically add multiple or the same item to your cart).
Off-grid PV System Shopping List
- 6 100 Watt Solar Panels ($649.99 for 6)
- MPPT Charge Controller ($189.99)
- MT-50 Remote Meter ($29.99)
- *Battery Temperature Sensor and USB Adapter ($11.90)
- 4 100AH Might Max Batteries ($174.99 each)
- 1 100amp Victron Battery Protector ($60.35)
- An on off switch ($8.48)
- AIMS Pure Sine Inverter ($169.00)
- *AIMS remote switch ($27.43)
- 150 amp breaker ($27.58)
- 50 amp in-line breaker ($12.99)
- 1 10 amp in-line breaker ($11.29)
- *1 fuse box ($39.92)
- *2 energy meters ($18.75 each)
- About 2 packs of copper ring terminals ($10.99 per 10 pack)
- Welding cable ($36.80)
- Lug Crimping tool and cable cutter ($28.98)
- MC4 connectors ($8.99 for 5 pairs)
- 10 gauge solar panel wire ($39.00)
- *A few of these USB 12-volt outlets ($7.99 each)
- A 10 amp AC breaker ($16.99)
- *12 gauge wire ($16.95)
- *Terminal connectors ($6.83)
Items with * are optional depending on your needs, but you're probably going to need them.
Total cost: $2,212.86
Just over $2k may sound like a lot, but believe me trying to go cheaper is just going to cause you a lot more problems than it's worth.
How to Wire Everything:
Basically I wired the 6 solar panels in series (believe me it's much more efficient this way than a parallel wiring, but you absolutely need an MPPT controller for this to work). Then I followed all the directions on wiring that came with everything else. For the most part it was pretty straight forward.
I will provide a detailed wiring diagram here once I get it drawn up. Also, if you ever need more power you can safely wire 8 100 watt solar panels to this same system instead of 6, but you'd have to wire them in sets of 4 in series then parallel the two sets. The maximum output charge power of this controller is 520 watts, but it can safely take solar arrays that are rated much higher.
It's important to know that a 100 watt solar panel almost never produces 100 watts (this is an absolute maximum rating under controlled conditions). With 600 watts of solar panels the most current I've ever seen flowing into my batteries is about 420 watts and that was when using a microwave on a very sunny day.
The amount of power flowing into your batteries doesn't just depend on your solar panels, it also depends on how charged your battery is. Charging a battery is like blowing up a balloon: the more full the balloon gets the greater the pressure required to fill the balloon. So, the more charged a battery gets the less current can flow into the battery. You will only see the max current flowing into your battery when it is at its lowest state and the panels are in direct sun light. You will also see higher currents flowing into your battery when there is a high current flowing out of your battery.
I installed two power meters in my system: The top one shows the power flowing out of the battery bank, and the bottom one shows the power flowing in. It also shows the energy stored in the battery and the energy used from the battery. The energy flowing into the batteries will always be higher than the energy flowing out of the batteries because batteries are not 100% efficient and lose a lot of energy as heat. You can see how efficient your batteries are by taking the energy out and dividing it by the energy in. Your batteries will become less efficient as they age.
I will provide a detailed wiring diagram here once I get it drawn up. Also, if you ever need more power you can safely wire 8 100 watt solar panels to this same system instead of 6, but you'd have to wire them in sets of 4 in series then parallel the two sets. The maximum output charge power of this controller is 520 watts, but it can safely take solar arrays that are rated much higher.
It's important to know that a 100 watt solar panel almost never produces 100 watts (this is an absolute maximum rating under controlled conditions). With 600 watts of solar panels the most current I've ever seen flowing into my batteries is about 420 watts and that was when using a microwave on a very sunny day.
The amount of power flowing into your batteries doesn't just depend on your solar panels, it also depends on how charged your battery is. Charging a battery is like blowing up a balloon: the more full the balloon gets the greater the pressure required to fill the balloon. So, the more charged a battery gets the less current can flow into the battery. You will only see the max current flowing into your battery when it is at its lowest state and the panels are in direct sun light. You will also see higher currents flowing into your battery when there is a high current flowing out of your battery.
I installed two power meters in my system: The top one shows the power flowing out of the battery bank, and the bottom one shows the power flowing in. It also shows the energy stored in the battery and the energy used from the battery. The energy flowing into the batteries will always be higher than the energy flowing out of the batteries because batteries are not 100% efficient and lose a lot of energy as heat. You can see how efficient your batteries are by taking the energy out and dividing it by the energy in. Your batteries will become less efficient as they age.
Tips on Building Your System:
You want the components of your system to be somewhere where they can maintain a decent working temperature and so air can flow around them, yet at the same time you want to mount them in such a way that makes the length of your wires as short as possible. Shorter wires means less electrical resistance.
- Make wires as short as possible to reduce electrical resistance.
- Use as high of gauge wire as possible for high current areas (battery cables, charging cables, etc.). Higher gauge wire means less resistance.
- Use a low power fan for ventilation.
- Using a vice carefully bend the battery cable terminals to right angles before crimping them. This makes it so you can make much shorter battery cables. You can buy right angle lugs, but they are way more expensive and they are way easy to bend.
- Use heat shrink and securly crimp all wires
Here are some pictures of how I wired my system together:
![]() |
Ignore the fact that the battery cable on the upper right corner is black (it should be red, but it was getting dark). |
Simple Rotating Solar Panel Stands:
![]() |
Dig a 2ft hole and cement a 7foot corner post into the ground. |
![]() |
Buy two of these for each post. |
![]() |
Cut 4 6" pieces of 2.5" PVC Conduit |
![]() |
Stick the pipes together with couplings (these stop the brackets from sliding down the pipe) |
![]() |
Slide the metal post clamps and pipe sections over the post. I added some grease to make it turn easier, but it turns out it's completely unnecessary. |
![]() |
Secure two 2ft sections of Super Strut to the top of each pipe section using 2.5" pipe brackets. |
![]() |
Attach 4 angle brackets. |
![]() |
Cap the post. |
Buy some zink-platted slotted angle bars to connect the solar panels together and bolt them onto the angle brackets as shown:
![]() |
I had these short metal plates I used to extend the reach of the top angle brackets, but they probably aren't needed. |
Tuesday, August 22, 2017
Solar Eclipse
So the solar eclipse was kind of interesting. It got pretty dim here. The voltage on my solar panel array dropped from 120 volts to 16 volts. It also got significantly colder. I felt myself grow uneasy for some reason. Maybe it's because the eclipse reminded me how much life depends on energy from the sun and a glimpse into a world where the sun isn't quite as bright was somewhat frightening.
Anyway, I didn't have special eclipse glasses so (without looking at the sun) I used my cellphone camera to view the eclipse and take some pictures. Now the sun was way too bright to view the eclipse directly with my camera but by angling the camera lens I was able to view the eclipse through the lens' internal refraction of the sun light. That's why you see two suns in this picture.
Subscribe to:
Posts (Atom)