If we go by Tesla’s new Tiny House project, you need six solar panels that feed 2.1kW to its Powerwall batteries for later use. On the other hand, the general consensus is that 15 300-watt solar panels will produce enough energy for a typical tiny house.

Figuring out how many solar panels you need for your home using just square meters can be challenging. Other factors also come into play when calculating the number of solar panels you need.

A tiny house's energy usage is approximately 920 kilowatts per year. The number of solar panels required depends on how many people live there and the energy needs of the tiny home. Your location also determines how much sunshine your solar panels get. 

Still, you cannot assume a tiny house will have a low energy load!

Moving to a tiny house may be the solution for those who want to stay out of debt. For every three tiny homeowners, two are not paying a mortgage. It might be a way to keep off the grid or a solution for empty nesters who want to travel the world. It could also be an opportunity for those who graduated with a student loan to save and pay off their debt. 

This post will cover how many panels you need for your tiny home and will detail the benefits of solar panels, including the solar options for your tiny home. It will also walk you through the cost of installing solar panels for your tiny house.

Tiny home fitted with solar panels on the roof

Benefits of solar panels for tiny houses 

Investing in a solar system allows you to save big on electricity bills. You protect the environment and have a reliable source of energy.  You even make some cash savings from the extra power you send to the grid. 

1. Power independence living off the grid

If you connect your tiny house to the grid, you rely on a utility company. That can be inconvenient during power blackouts. Yet, it is a good thing during the long dark hours of winter or at night. There is no sunlight to power your solar panels then.

Buying solar gives you independence from the grid. You produce your power for self-consumption.  

You'll get more value from your solar when you add batteries for extra energy storage.

2. Save money from utility bills

A major benefit of buying solar is the cost savings on your utility bills considering electricity rates are ever rising.

3. Tiny homes save the planet

Tiny homes are eco-friendly. They protect the environment by reducing pollution, wastage, carbon emissions, and creating renewable energy. As a tiny homeowner going solar, you play a critical role in saving the planet.

4. Benefits from government incentives and solar rebates

Government and states subsidize the cost of solar through incentives and solar rebates.

Australians reduce their upfront solar costs with federal and state governments' incentives whereby you qualify for free solar and battery installation, a feed-in tariff, and STCs. Other incentives include low-interest loans or interest-free loans.

If you are in the US, you’ll enjoy a 26% tax credit until 2023, when the tax credit decreases to 22%. There won’t be a tax credit incentive for residentials in 2024, which is why you should buy solar now.

Biden’s administration is pushing for a 30% Investment Tax Credit (ITC) for the next ten years. Plus a solar batteries Federal Solar Tax Credit. Be on the lookout to see if it comes to pass.

The Solar Renewable Energy Certificate is also available in 38 States for each 1000kw/h. Income from SREC is, however, taxable.

Additionally, twenty-five states also have solar tax exemptions. Thirty-six states have property tax exemptions. You realize your tiny house value appreciates when you install solar. Find out more on solar tax exemptions here.

5. Make some money by selling your extra power

Tiny homeowners' solar systems without a battery system have excess power. They send this power to the grid in exchange for credits. You could pay 0 kilowatts when your credits and energy usage balance.

Also, you make some money from the solar feed-in tariff depending on your location. Find your solar feed-in tariff here by clicking on your state if you live in Australia.

In the US, the arrangement with your utility company is net metering, and it works the same.

6. Added value to your tiny home

Buying and installing solar on your tiny home increases its market value. Buyers are willing to pay extra for that clean, renewable energy.

7. Freedom

A tiny home on wheels with solar is self-reliant. You don't have to worry about power for heating, cooling, or cooking when on the move. You simply harness the energy from the sun, even in remote areas.

How many solar panels do you need for your tiny house?

You need three solar panels on the low end and 15 solar panels on the high end. You can't figure out how many solar panels you need for your tiny house, even if you know how many square feet it is? You must think about how much energy you use and how many people will be living there. You should also factor in the roofing space, shading, panel efficiency, and location. 

Queensland, for example, the sunniest state in Australia, will have more solar production than other states. Same to California in the US.

Factors that influence the number of solar panels you need

1. Power consumption

Calculate how much power you use. You need to figure out how many watts you use per hour and the cumulative energy used per day.

Your power needs also depend on whether you are going wholly off-grid or still connected to the grid.

How many solar panels you need = Watt/hour X Sunlight hours / Panel’s Wattage

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2. Occupancy

Six panels averaging 250 watts per panel can cater for two people, cooking three meals a day using gas. The more people live in the tiny house, the more power you’ll need.

A little home uses 3killowatts to 4killowatts per day, assuming the average energy produced by one panel is 300 watts per hour. For approximately 5 hours of sunlight and 300 watts of power output per panel, you will need 15 solar panels to be self-sufficient. That’s 4500 watts.

3.  Solar shading and roof space

How much roof space you have will determine how many solar panels you can put on your roof if you opt for roof mounting. Pole and fixed ground are other solar mount options.

You should also consider how much sunlight gets to your panels. Avoid shading from trees and other structures. Fortunately, you can move tiny houses to take advantage of optimal sunlight.

Fifteen watts =1 square foot

 ?                    =Total roof square feet.

To get the number of panels needed, divide the total wattage by individual panel wattage.

Your roof may not have ample space for solar panels. That’s why mounting on the ground is favorable. The advantage of mounting solar on the ground is putting in as many solar panels as needed.

Second, you can easily clean them. Remove any snow on them during winter, increasing their efficiency.

4. Solar panel efficiency/wattage

Solar panels come in different sizes and wattages. Your solar panel wattage could produce anywhere between 250 and 400 watts per hour. 

After calculating your power consumption, divide that figure by the wattage of each panel to get how many solar panels you need.

Some high-efficiency solar panels are more expensive than your ordinary PVs. That's because they produce more power on a lesser surface compared to regular solar panels. These are good for situations where shading cannot be avoided. 

Factors that determine solar panels' efficiency include temperature, orientation, maintenance, solar shadings, and energy conversion efficiency per panel.

5. Location or orientation

States in the Sunbelt or southwestern states like Florida, Arizona, generally get more sunshine hours. If your tiny home is in the Nothern hemisphere, tilt your panels to the true south for the PVs to get direct sunlight. Southern Americans tilt them towards the true north.

For best results, ensure the sun rays hit the panels perpendicularly throughout the day by tilting them in the right direction. If you are at 40 degrees longitude, tilt them at 40 degrees. 

The direction is longitudinal direction island, not magnetic compass directions. Use a map.

TABLE: Daily average solar panel output (kWh) by states in the US

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Assuming you are in Florida, the global horizontal irradiation is 5.079. So during peak hours, a 300 solar panel will generate 1.52kWh/day.

To get how many solar panels you need, divide your estimated power need by this figure 1.52kWh/day.

Then multiply what you get by 300 for total solar production in a day.

Australia is in the southern hemisphere, meaning optimal solar power is achieved when panels face north. Different states, however, have varied solar outputs.

 Source: Clean Energy Council Consumer Guide page 4

The tabulation shows how much solar output your panels may produce daily in Australia. With total power consumption, you can use this to get the number of solar panels for your tiny home.

Other factors in solar production are battery amperage, the panels' and batteries' series or parallel connection, and inverter size.

Solar options for your tiny house

Tiny solar homeowners can either go the do-it-yourself route or seek the services of a solar installer. How much energy you require will determine your choice.

The solar payment options in the US are cash payment, solar loan (payable with interest), and lease. The first two are eligible for federal and state incentives, but the lease option is not.

The DIY option

If your power usage does not go beyond 3kW per day, consider DIY solar systems complete with a solar battery and a backup generator if you choose to go completely off-grid.

The first step in the DIY solar option is to calculate your power needs. When calculating your daily energy usage, ask yourself, “How many appliances do I want to power? Will I be self-reliant and off the grid?”

Answering these questions will help you determine your power needs, and consequently, how many solar panels you need.

Going off-grid, however, is a big step that might call for a complete change of habits or doing away with appliances that take up much energy. You might have to use gas for cooking and heating to supplement the solar or downgrade on appliances.

Still, you can get more solar panels at a higher cost if you want to keep some appliances like your coffee maker.

Second, purchase your solar system components. Buy batteries, inverter, solar panels, racks, and backup generators if you won't be depending on the grid. You can find everything you need to know about these components here. 

Thirdly, ensure you have the necessary permits and the design of your solar panels. Also, by now, you must be aware of the rules on tiny homes with wheels and building permits for stationary ones.

The next step is setting mounting equipment. You can build a rack on the ground if you don’t plan on moving a lot. You can also mount the stands on a different trailer if your roof space is insufficient.

Connect your solar system starting with the inverter, panels, and batteries. Join this with your main electrical board. 

You should hook the inverter and controller to a proper breaker system to function well. The user manual for a DIY kit has a diagram of how everything should look.

Then look for inspectors who will verify that you did your installation right. They will give you a meter after connecting you to the grid if you plan on linking to the grid to get power at night. Remember, you need to apply for them to join you with the grid.

Some areas in Australia require getting a PTO order ( Permission To Turn On).

After that, you are all set, and you can use a monitoring app to determine your power production and energy usage. 

Solar installer

This is the easier option where you get a solar installer to asses your tiny home and give you a free quote.

Before settling, ask for federal and government incentives you could take advantage of, loans, and payment plans.

Ask for references or recommendation letters for their company, brand preferences, and warranties.

You can get several solar quotes and compare the prices. Price, however, should not be the only determining factor, and reviewing recommendations and experiences could be pretty helpful.

After looking at all these factors, settle on one solar installer and go over your installation and payment plan again.

What is the cost of installing solar panels on a tiny house in Australia? 

Installing a typical rooftop solar PV system can cost anywhere from $3,000 to $12,000. That depends on the solar panels' wattage or type and your location. That figure could also waver depending on the components of your solar system, such as inverters, batteries, power consumption, and installation costs.

These prices consider government STC (Small scale Technology Certificate) incentives for small businesses and homeowners.

Here is a tabulation of the estimated costs of solar in Australia in each state.

Average cost of solar in Australia

Factors that determine solar cost

As you might have noted by now, your location and the type of solar system you want are the most significant determiners of solar cost.

Other factors that might affect how much money you part with include:

Connection to the grid fee

The linking cost of your solar system to the grid is often referred to as interconnection fee. You pay the fee after getting the correct solar permits.

Orientation of the roof and its characteristics

In Australia, an old roof facing the south will incur more installation costs. So will a flat roof needing racks to tilt panels towards the north or south for optimal sunshine.

It is not easy to install solar on old rooftops. The more the effort to install solar panels, the higher the labor. A roof with maximum exposure to the sun's rays is easy to work with, and the price comes down.

Solar panel type and brand

High premium panels will cost you. Costs from different brands also vary. The brand type also determines the efficiency or quality of the solar panels. Highly efficient solar panels are more capable of producing energy from sunlight than their low-quality counterparts.

Solar installer costs

The installer you pick to assess your home power needs and install solar will charge you a labor fee. Sometimes that fee depends on demand and supply forces. When demand is high, the cost goes up.

Also, reputable installers charge a premium fee based on their expertise. 

Additionally, the further you are from the solar company, the more you may have to pay.

A solar inverter

An inverter converts direct current from your solar panel into alternating current. Your appliances use AC. Buying an inverter adds to your total solar costs.

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What is the cost of installing solar panels on a tiny house in the US? 

The cost of installing solar in the USA per watt is $2.94. The number of solar panels you get based on your energy requirements should get you the estimated total installation costs using the total wattage.

Use this table to see an estimate of solar installation costs by state.

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At $2.85 per watt and after the 26% solar tax credit you'll only pay $6,327 for a 3kW system.

Like Australia, factors affecting your total costs include solar incentives and location, type of solar panels, power needs, wiring, mounts or stands, batteries, and other equipment costs.

Your total bill should be lower than those 5kW systems, but inclusive of the cost of finance, should you take a low-interest loan. Most tiny homes will need 3kW or 4kW systems.

Conclusion

Buying solar power is a major decision that requires careful consideration and preparation.

Do your research by reading solar guides from at least two solar companies. Also, consider recommendations from other tiny homeowners.

Joining a tiny homeowners association to get such information will be a good idea.

The next step would be to calculate your power needs based on your utility bills over the years. A solar installer can help you with these. Consider all other factors before purchasing a solar system. These would be your location, the solar panels' efficiency, and tilting towards the sun.

Next would be to decide if you will do it yourself or would enlist the services of a solar installer. It is always a good idea to compare solar quotes from different companies. Once your solar panels are up, remember to maintain them by cleaning them. 

The benefits of a tiny home are worth it; saved costs, no debt, freedom, and protecting mother earth. Take advantage of the solar incentives and solar rebates now! 

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