Off-Grid Solar and Heating Systems For Tiny Houses

Living in a tiny house is an appealing option for many. One of the most significant benefits of living in a tiny house is a lowered consumption of resources, especially electricity. Even in a cold Canadian climate, a tiny house can be completely self-sufficient and off-grid if you build it correctly. This can be accomplished by utilizing a combination of two things, creating your own electricity (via off-grid solar) and using less in the first place. Creating your own electricity allows you to be completely off-grid. In most applications, solar power is the easiest way to achieve self-sufficiency. We will focus mainly on solar power in this article. SOLAR MODULES AND BIFACIAL SOLAR When installing solar panels, there are a few things to consider. Solar panels are most efficient in northern climates with harsh winters when positioned on a steep angle. This helps the panels receive more sunlight when the sun stays close to the horizon during the winter. Additionally, the tilt of the solar panels will prevent snow from accumulating on top and obscuring sunlight. There is no reason to limit yourself to installing solar panels on the roof. Wall-mounted panels are a viable option for many. An exciting new technology, bifacial solar modules, can increase the production of solar power systems. Bifacial modules differ from standard modules because they can produce electricity from both sides of the module. If your roof is reflective, bifacial modules can significantly enhance the efficiency of your system. CHARGE CONTROLLER   MPPT, or maximum power point tracking, is a technique used to convert energy from solar panels to batteries. MPPT changes both the voltage and the current to maximize power output. Generally, MPPT is much more efficient than PWM.

LITHIUM-ION BATTERIES IN COLD

While cold weather can negatively affect all batteries, lithium batteries are more cold-resistant than other batteries. We recommend using lithium as an extra precaution in cold climates.

SPACE HEATING

Next, you need to figure out how best to heat your tiny house. There are a few methods. You can heat your home with propane, but this is expensive for a tiny house since you will need a propane tank. Plus, propane is not a renewable resource. Another option, an air-source heat pump, works by pumping air from outside and heating it through a method similar to air conditioning, but in reverse. Air-source heat pumps are one the most efficient ways to convert electricity to heat.  For a more rustic atmosphere, you can also use a wood-burning stove to heat your home. For a tiny home, using a real wood-burning stove is probably overkill and not the most efficient, but it has many other benefits. For example, you can cook on a wood-burning stove, which is arguably the “funnest” way to cook anything. Additionally, a wood-burning stove is not reliant on electricity, so in the case of an outage, you can keep your home warm.

PASSIVE SOLAR

If you design your home correctly, you can produce heat directly from sunlight, even in the winter. This is called “passive solar.” There are too many passive solar techniques to go over in this article, but we’ll cover the basics. The most important thing is to have large windows that face south to let in the sunlight. You also need to have a calculated overhang that will keep the sun out in the summer, when the sun is high in the sky, and let the sun in during the winter, when the sun hugs the horizon. It also helps to minimize windows on the north side of your house to help contain the heat. The final, and maybe the most important step, to have efficient heating is adequate insulation. If you are lucky enough to experience hot summers where you live, you can place one or two windows that open on the east and west side of your house to create a through-breeze. If you are lucky enough to have trees where you live (sorry, prairie provinces), then you can plant a few outside of your windows to provide shade in the summer and let light through in the winter.

SOLAR WATER HEATING

Unless you enjoy the splendours of hypothermia each time you take a shower, you will probably want to heat your water. You can use thermal solar collectors, a technology that collects heat directly from the sun. You can also simply heat your water with electricity and a hot water tank. A not so obvious use for hot water is to run it through pipes in your floor in order to help provide heating throughout your home. This sort of in-floor heating is very effective in tiny houses. A frequent problem with solar power systems is that once the batteries have been fully charged, all the generated power is left with nowhere to go and is discarded. A clever way to get around this issue is to transfer your excess electricity into hot water instead and store the heat rather. As an extra precaution, you should keep your water-related appliances near the centre of the home so that they are the last to freeze in the case of an outage. It is necessary to take all the extra measures if you plan to have your home off-grid. Water expands when it freezes, and copper pipes do not perform well under pressure, whereas PEX or plastic pipes can stretch a little and remain intact.

DC FRIDGE AND FREEZER

When choosing a fridge for your home, remember that DC fridges are more compatible with solar panels. Solar panels produce electricity in DC, and each time you convert DC into AC, you lose energy. Choosing DC appliances can significantly increase your efficiency. You should also consider the placement of your fridge. There is no need to heat your house and then use more electricity to cool your fridge. We would recommend placing your fridge on the fringes of your home, possibly even within your wall. Since sunlight is more abundant in the summer, your electricity will be worth more in the winter. It is more efficient thus to cool your fridge in the hot summer months than to heat it up and then cool it down in the winter.

BACK-UP POWER 

Building off-grid solar is all about risk management. We would recommend having a backup generator in the case that the weather is cloudier than usual or something else goes awry. A backup generator can be anything from a diesel or propane generator, a micro-hydro generator, or even a wind turbine. It does not have to be big, just enough to keep the necessities running. Diesel generators are more reliable in the cold Canadian winters; however, they also demand more maintenance. Micro-hydro and wind turbines are renewable, but they are also intermittent, just like solar. Depending on the day or season, the abundance of wind or water will fluctuate. Building a tiny house off-grid can be a daunting task. Hopefully, this article has helped you understand how best to go about building one. If you have any questions, do not hesitate to reach out to us. We wish you the best in your construction.   Building a tiny house off-grid can be a daunting task. Hopefully, this article has helped you understand how best to go about building one. If you have any questions, do not hesitate to reach out to us. We wish you the best in your construction.