Tiny Houses & Electricity: Facts About Generators & Solar Panels

In Tiny Houses (on wheels)by Christopher Schopf

Tiny houses don’t have to have tiny electricity capacities.  Generators and solar panels can be used for off-grid living and standard electricity panels can be used while hooked up to the grid.

In this post, we’ll go over tiny house electricity needs and talk about exactly how generators and solar panels can help to meet these needs.

We’ll even offer up some alternatives so that you can still meet all of your needs without running out of electricity.

Electricity Requirements For Tiny Houses

The first step to take when considering generators and solar panels is to think about your actual electricity needs.  What will you be powering and how long will you be powering it for?

I’ve seen many tiny houses that have all the amenities of a larger home.

These tiny houses have washing machines, dryers, dishwashers, large hot water heaters, and a lot of interior and exterior lights.  Often-times, these houses will be heated and cooled by mini-splits which also require a lot of electricity.

A tiny house like this might use almost as much energy as a traditionally sized house.  The U.S. Energy Information Administration puts this at about 867 kWh per month or about 29kWh per day.  Unfortunately, generators and solar panel systems are not going to meet these kinds of needs.  This means that if you’re going to run your tiny home off of a generator or solar power system, you’ll need to change the way you do things.

Here are some examples of what the average appliance uses in electricity per day.

Heating In Tiny Houses

An electric furnace uses up to 10.5 kWh per hour while a portable heater uses about 1.5 kWh per hour.  Tiny homes are often small enough to be heated by a small portable heater or two so you’ll probably want to factor in about 1.5kWh when estimating your heating costs.

This doesn’t include hot water though so you’ll need to factor this in as well.

A standard home’s hot water heating instant system uses 12kWh per hour.  Ten minutes of hot water usage a day would result in about 2kWh being used each day.

Here’s a complete guide to heating in tiny houses (with recommendations).

Cooling

A small window AC unit is probably all you’d need in a tiny home but it will still consume about 1kWh per hour of run-time.

Run your AC unit for 20 minutes each hour and you’ll end up using about 8kWh per day.

Cooking

We’re going to assume that you are using gas cooking but you’ll still need electricity to run your refrigerator.  A new 14 cubic foot refrigerator will use about 34.5 kWh per month which puts you at about 1.1 kWh per day.

This, of course, assumes that you are using an electric refrigerator.  You could choose to buy an RV refrigerator which can run off of gas as well as electricity.

This also assumes that you won’t be using a microwave or coffee maker.  These appliances are power-hungry so if you decide to use them you’ll have to factor in even more electricity use per day.

Electronics

Will you be watching television or using a laptop inside your tiny home?  A laptop will use about .05 kWh per hour and a 40″ television will use about .4 kWh per hour.

Stereos, gaming systems, desktop computers, and traditional computer screens will consume power as well.

Laundry Appliances

A dryer can use up to 4 kWh per load and a washing machine can use up to 6.3 kWh per load.  You can cut this number in half if you run small loads with a warm wash and a cold rinse cycle versus larger loads with a hot wash and a warm rinse cycle.

What to do With This Information

These numbers will help you determine how much solar you’ll need as well as what size generator you might want to buy to help power your tiny house.  Without knowing how much energy you consume, it is very difficult to buy an appropriately sized generator.

Overestimate how much energy you use and you’ll end up buying a generator that is too big.  Underestimate how much energy you use and you won’t be able to power all of your electrical devices.

We’ll take a further look at how generators and solar panel systems work as well as how much electricity you can expect to get from them in the next two sections of this post.

Don’t be alarmed if it seems like you’ll never be able to get enough power as we’ll talk about how to meet your needs without using a lot of electricity in the section right after this.

Generators For Tiny Houses

There are many different types of generators you can buy to power a tiny house.  Tiny house generators are the same generators that you might use to power your RV.

These generators can be fueled with electricity, gasoline, diesel fuel, and even propane.  The most popular of these generators is the diesel fuel generator as that typically comes with the highest electricity ratings and the cost of fueling this type of system is usually more reasonable than using the other types of fuels.

Also, electric generators tend to have small storage capacities and are better suited for emergencies rather than for everyday use.  Another reason for this is that you’d end up having to drive your tiny house somewhere to charge up your electric generator.

With the other types of generators, you just need to bring some fuel to your tiny home to power up your generator.

Find out how much fuel a generator uses on our post titled, “How Much Fuel Does an RV Generator Use“.

What Size Generator do You Need?

If you read the section on electricity requirements, you’ll have a general idea of how much energy you use in a day.  However, you’ll also need to know how much energy you tend to use at one time.  This is because generators typically have max wattages that need to be strictly adhered to.

For example, if you buy a 1,500-watt generator and try to run a 1,500-watt space heater along with a television, you’ll end up going over the generator’s watt capacity.  In this case, you’ll probably end up tripping your electrical breaker and then none of your electrical systems will work.

Try to determine how many appliances you’ll have running at one time and do some addition to determine the wattage capacities you’ll need at any given moment before shopping for generators.  This will give you the information you’ll need to determine what wattage you’ll have to buy.

You’ll also need to think about fuel capacities as well.  People who use a lot of electricity will want to buy a generator that can store a lot of fuel in its tank.  This will help keep you from having to pour fuel into your generator as often.  It will also reduce the number of auxiliary fuel storage containers you need to have on hand.

Find out how much fuel a generator uses on our post titled, “How Much Fuel Does an RV Generator Use“.

Solar Panel Systems

Solar panel systems are very popular on tiny homes.  These are usually placed on the roofs of tiny homes but they can also be built into a solar array placed in an open area or even on top of a solar shed.  The placement of your solar panels will largely depend on where you’re parked, how long you’re parked there, and how many panels you plan to use.

Stationary tiny homes can take advantage of solar fields and solar sheds.  This gives the owner the ability to put the solar panels in areas with the largest amount of sun while still being able to park their tiny homes in the shade.

Often-times, these solar panels will be built onto frames that will rotate based on the position of the sun.  The shed can hold the batteries so that the tiny home does not have to use up additional storage space inside.

Tiny homes on wheels will usually have larger solar panels placed on top of the roof or along the walls of the tiny home.  These panels will generally range from 100 watts to 400 watts.  Smaller removable panels can also be used so that the tiny homeowner can get additional sun when the tiny home is in a less than ideal location.

Solar panels can charge batteries which can run DC powered appliances directly.  For AC appliances, an inverter will need to be used.  Batteries can also be charged from the grid using a converter.  You can read more about inverters and converters on my post titled, “How do RV Inverters and Converters Work“.

Getting Enough Power from Solar Panels

Generally, solar panels on tiny homes will only be used to run electronics and refrigerators.  Appliances like washing machines, dryers, dishwashers, and microwaves use up more electricity than most solar panel systems can create each day.

Heating and cooling generally don’t work very well with a solar power setup either.  You could use the solar panel system to run a fan to keep cool and a fan to push forced air through a gas powered system but you wouldn’t want to power window AC units or portable electric heaters with solar power.

Here is an example of how much energy you might expect from a solar power system.

A 100-watt solar panel might be four feet long by two feet wide.  This means that you won’t be loading your tiny house up with 50 of these panels.  If you’re lucky, you may be able to get about 2,000 watts of panels.  With eight hours of sunlight, you may be able to get 16,000 watts of power but most solar panels are not 100% efficient.

Even if you get 16,000 watts of power, you’ll need to store this power.  If you bought ten 12 volt/140 amp hour batteries, you could capture this much energy.  However, batteries should never be drained down to zero so you wouldn’t be able to use all of this energy.  You’d actually be able to use about half of this which would be 8,000 watts of energy.

I’d say that with ten 100 watt solar panels and ten batteries you could successfully get to this 8,000-watt number but this would be twice as much solar as most tiny homes tend to have.

Remember, these batteries might weigh 50 pounds each so ten of them will add 500 pounds of weight to your home.  The panels are also large so you might have trouble finding the roof space for ten panels on a smaller tiny home.

Unfortunately, even 8,000 watts of solar probably won’t be enough to run your tiny home the way you might run a regular home.  The average home uses 29 kWh so your 8 kWh isn’t even going to provide 1/3rd of a home’s average needs.

Luckily, there are a few steps you can take to reduce your electricity needs.

Meeting Your Power Needs

The easiest way to meet all of your power requirements while still relying on a generator or solar panel system is to simply do without.  Hand-wash your dishes, line dry your clothes, and wash them by hand and you won’t need to power any of these power-hungry appliances.

You could also switch to low-energy appliances so that even when you do use these appliances, you aren’t using as much power as a standard home would.  Also, refrigerators can be smaller which will also reduce the amount of energy used to keep your food cool.  After all, many of us don’t even use most of the space in our large refrigerators anyway.

You could also switch from watching television to reading books and you wouldn’t have to worry about powering a TV either.

If you’re worried about climate control, you could choose to live someplace mild.  People living in Southern California never need heat or air conditioning.  If you get a little cold, put a sweatshirt on.  If you get a little too warm, take off a few layers and sit in the shade.

You could also consider switching to gas-powered appliances (see our recommendations here).

Mr. Heater gas heater

Gas heaters and gas refrigerators work just as well as electric ones and they run on gas instead of electric.  Taking all of these steps could easily bring your power consumption needs down to 2 – 4 kWh per day.

Your life may be a little less convenient but you’ll have less impact on the environment and you won’t have to worry about being connected to the grid.

Generators and Solar Panels

One way to ensure that you’ll always have power is to have a generator as well as a solar panel system.  With a system like this, you can get free energy from the sun on most days and take advantage of your generator on days when it is not as sunny.

You could also use your solar panel system to run most of your everyday appliances and only use your generator on days when you want to use your laundry appliances. 

A rare hot or cold day in a mild climate and you could turn a heater or AC unit on while running your generator.

This is probably the best of both worlds as you’ll always have some power via the solar system even when you are off-grid and away from places to buy generator fuel from.

Connecting Your House To The Grid

If you’ve decided that being connected to the grid is the only way you can meet your power requirements then you’ll need to set your tiny home’s electrical system up like an RV.

You’ll probably want to go with a 50 amp system so that you can run your laundry appliances but you could go with a 30 amp system if you’ve decided not to use them.

With this setup, you’ll run AC power throughout your tiny house and you’ll be able to plug in and use all of your electrical appliances to your heart’s content. 

If you also want to add a battery bank, you can put in a converter and an inverter so that you’ll have some power while traveling to and from your destination.  This is also nice to have in case of an emergency or power failure as you’ll at least be able to keep your refrigerator running.

For more information on connecting a tiny home to the grid, see my post titled, “Do RVs Need to be Plugged In“.  This post goes over 30 amp systems, 50 amp systems, and even how to use a standard outlet to plug your tiny home into the grid.

Apply this RV knowledge to your tiny home and you’ll learn everything you need to know about powering your tiny home.

In Closing

Generators, solar panel systems, and grid-tied systems all have their plusses and minuses.  Determine what your energy needs are and decide on what kind of lifestyle you want to live before committing to any one type of system.

Also, remember that you don’t have to be limited to one type of power source. Check all the alternatives here, when it comes to heating a tiny house.

Many people have opted to create grid-tied systems that can be powered through solar energy as well as power generated from a generator.  RVers have been using setups like this for years and it has helped their owners to get more enjoyment and versatility from their rigs.