Solar how much power do i need

How many solar panels do I need for a 3-bedroom house? How many solar panels do I need for a sq. These are all common questions for an aspiring solar homeowner. Do you want to minimize your carbon footprint? Maximize the return on your investment? Save as much money as possible? Note that the size of your roof and how much sunlight your roof gets are factors as well.

If you work with an experienced solar installer, they will handle all these calculations for you. You can use SunPower Design Studio to estimate your own system size, monthly savings, and the actual appearance of a solar array on your own roof.

This interactive tool provides a solar estimate in just a few seconds and can be done on your own or on a call with a SunPower Look at your electricity bill for average usage.

Your answer will be in kW. A small home in a temperate climate might use something like kWh per month, and a larger home in the south where air conditioners account for the largest portion of home energy usage might use 2, kWh or more.

The average U. Your average daily energy usage is your target daily average to calculate your solar needs. The peak sunlight hours for your particular location will have a direct impact on the energy you can expect your home solar system to produce. For example, if you live in Phoenix you can expect to have a greater number of peak sunlight hours than if you lived in Seattle.

The Renewable Resource Data Center provides sunlight information by state and for major cities. Now multiply your hourly usage see question No. To ballpark this figure, find the average daily peak sunlight hours in your state. North Carolina receives an average of 4. Since 1 kW equals 1, watts, our next step is to multiply our kilowatt number by Lastly, we must divide the number of watts of the system by the number of watts one solar panel generates.

Ultimately, the number of solar panels you could need to see potential savings is unique to you. Request a free quote today to determine how many panels you could need to see potential savings or learn more about how solar panels work on your home. New customers only. You are still responsible for paying your monthly loan to your lender.

Rebate not applied toward your loan by us. Allow wks. The amount of power available from the battery during a power outage is limited, depending on the loads connected, customer usage and battery config. No assurances can be given that the solar system or battery will always work. You should never rely upon either to power life support or other medical devices.

To qualify, you must have federal income tax liability at least equal to the value of the tax credit. We make no guarantees regarding eligibility for any tax credits. Put all this together and you should have a good understanding of how much power you usually use each day, how much you use on peak days, and the times of day you use the most power.

Your solar PV system is hopefully going to be on your roof for many years to come, so you want to try to anticipate how much electricity you'll likely need in the future too. Some future needs to consider are:. Don't worry, you don't need a crystal ball for this. The simple solution is to put on as big a system as you can reasonably afford right now, as we discuss further down.

And it can be possible in many cases to upgrade or expand your solar PV system in the future. Now you know how much power you typically use and the times of day you use it.

What capacity will your solar PV system need to be to cover your power usage? First, we're assuming you'll have a grid-connected system. This is by far the most common type and it simply means you have solar panels generating electricity during the day, and a grid connection to supply electricity when the solar panels aren't generating enough at night, for example.

See grid-connected vs off-grid for more. Solar PV systems are rated in watts W or kilowatts kW. You'll see systems described as 4kW, 5kW, 10kW and so on. See terminology for the difference between a kilowatt — how the solar PV system is rated — and a kilowatt-hour, the unit by which your consumption is measured and billed.

For each kW of solar panels, you can expect about 4kWh per day of electricity generation. It's just a general rule — the actual amount of electricity generated per kW of solar panels depends on your location, the time of year and the amount of sunlight you're getting, the quality of the system, the orientation of the panels, how old they are, and so on.

In southern regions such as Hobart it could be as low as 3. Your minimum aim is to cover as much of your household consumption as reasonably possible for a typical day. If your power consumption is say 30kWh on some days, but on most days it's 20kWh, it might not be worth adding extra panels just to cover those few 30kWh days. You could go with a 5kW solar PV system and just accept paying for more power than usual from the grid on those occasional high-consumption days.

But solar panels are relatively cheap now, and there's an economy of scale in installing a larger system, so it's worth talking this through with your installer to consider how big a system you could get.

Typical solar PV systems installed in are at least 6. That said, bigger systems of 8—10kW are becoming more common, especially for systems that include a storage battery.

You might think it's better to oversize your system because any excess will be exported to the grid, and you'll be paid for it via the feed-in tariff. But the feed-in tariff for new solar PV systems is generally very low — typically from four to eight cents per kWh, though you can get better deals from some energy retailers — and it's unlikely on its own to justify the cost of a larger system.

The real benefit of a larger system is that it will be easier to add a battery, take full advantage of your inverter's capacity, and simply to generate more power throughout the day so that you are less likely to need grid power. And the excess power that you're sending into the grid will mean there's more solar-sourced electricity in the system for other homes to use.

Since you're looking at saving on power costs by installing solar, it makes sense to maximise your use of that solar power. So as much possible, your electricity consumption should happen during the day when the panels are generating. The grid will absorb any electricity generated by the solar panels not used by your home. When you are using more electricity than can be produced by the sun and at night, of course , the grid automatically tops up your electricity needs.

As I explained previously, when you use electricity is almost as important as the amount of electricity you use. Getting zero bills with only solar panels — and no battery storage — is possible. Until I added an electric car to my home, I regularly got credits on my electricity bills. Yup — my retailer was paying me for the privilege of being connected to the electricity network!

If this home could fit more than 6. You can see all of the DNSP rules for each state here. Meaning — if you have a single-phase home in SA, you could have up to