How Many Solar Panels Do You Need For 1000 kWh Per Month?
How Do I Calculate How Many Solar Panels I Need?
- Estimate your home’s energy usage in kWh per day
- Find the irradiance value in kWh/m2/day (peak-sun-hours) for your location
- Calculate the theoretical size of the solar system needed in kW
- Adjust the system size to account for losses
- Divide the final kW solar system size by the individual solar panel watts
- Add another 10% to account for periods of bad weather
A home consuming 1000 kWh per month would need 27 solar panels, each rated at 300 watts. This assumes an average irradiance of 4 kWh/m2/day (peak-sun-hours) and does not include PV system losses of up to 23%. Good practice is to add 20% to 25% more panels to account for system losses.
Video – How to calculate how many solar panels you need for 1000 kWh per month
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How Many Solar Panels Would I Need For 1000 kWh Per Month?
Every solar calculation begins with the load, in this case 1000 kWh. You begin by working out how many kilowatts of solar power would be needed, before calculating the number of solar panels.
It sounds easy, but there are a few things you need to know.
First of all, solar panels don’t put out the same power in every location – it depends heavily on the irradiance, or sun’s energy, in your geographic location.
Secondly, the theoretical power output from a solar panel array is never what you actually get! This is because there are losses in all solar power systems. These losses can be around 23% of the total output, so not insignificant.
Infographic – Solar Panel Sizing Takes 10 Major PV Losses Into Account
By far the biggest factor affecting solar panel output is irradiance, and this varies by geographic location.
The two worked examples following show the difference in the number of solar panels needed for a home using 1000kWh per month in San Francisco, Ca and Glasgow, UK.
How Many Solar Panels Do I Need For 1000 kWh Per Month In San Francisco, Ca?
How many solar panels needed for 1000 kWh in San Francisco is hugely affected by the high irradiance
Solar calculation – panel sizing for San Francisco:
- City: San Francisco
- Home energy use: 1000 kWh per month
- Solar system losses: 23% (same as multiplying energy needs by 1.4)
- Solar energy required per month: 1000 kWh x 1.4 = 1400kWh/month
- Solar energy required per year: 1400 kWh x 12 = 16800kWh
- Irradiance at San Francisco, Ca = 2089.1 Peak Sun Hours/year
- Solar system size required: 16800kWh/2089.1 PSH = 8.042kW
- How many 300 watt solar panels required?: 8042 watts/300 watts = 27 solar panels
What is the solar system payback period in San Francisco?
Installation costs for a solar power installation in SF is about 2.5 per kW, so the cost of an 8.042kW system would be about 20000.
In the calculation below, I’ll work out how many years it will take to recover that capital cost:
- San Francisco residential electricity cost per kWh = 25.7 cents/kWh
- Yearly savings = energy usage x electricity cost = 12000kWh x 25.7 = 3084/year
- Solar payback time San Francisco = solar cost/yearly savings = 20000/3084 = 6.5 years
Renogy Solar Panels – Innovation Meets Quality
How Many Solar Panels Do I Need For 1000 kWh Per Month In Glasgow, UK?
There should be a big difference in the number of solar panels required in Glasgow, because the irradiance is much lower than in California – see the screenshot from GlobalSolarAtlas.info below:
Hoe many solar panels would you need to power 1000 kWh in Glasgow, UK?
The Direct Normal Irradiation 678.8kWh/m2/year (also called Peak-Sun-Hours) in Glasgow is more than 3 times less than in California. Now let’s do the calculation again:
Solar calculation – panel sizing for Glasgow, UK:
- City: Glasgow, UK
- Home energy use: 1000 kWh per month
- Solar system losses: 23% (same as multiplying energy needs by 1.4)
- Solar energy required per month: 1000 kWh x 1.4 = 1400 kWh/month
- Solar energy required per year: 1400 kWh x 12 = 16800kWh
- Irradiance in Glasgow, UK = 678.8 Peak Sun Hours/year
- Solar system size required: 16800 kWh/678.8 P.S.H = 24.75kW
- How many 300 watt solar panels required?: 24750 watts/300 watts = 82 solar panels!
Clearly, this is a huge difference and it probably isn’t worth it to install solar in Scotland.
How Much Power Does An Average House Use?
1000 kWh is not far off the US monthly average for a typical home, which is 900 kWh/month. This equates to about 30 kWh per day.
How Do I Calculate kWh?
It is possible to estimate a home’s energy needs in kWh, but it isn’t very accurate. You would have to add up all the wattages of ‘normal’ appliances (you’ll see what I mean by ‘normal’ later on in the post.)
You also need to guess how many hours per day a particular appliance would be used. As you can see, the approach isn’t too accurate.
What I call ‘normal’ appliances are those with a constant wattage i.e. you switch it on and it takes a constant amount of power in watts.
How many solar panels would you need to run air conditioning?
Some appliances aren’t like that. If an appliance uses a compressor, such as refrigerators, heat pumps, freezers and air conditioners (AC), then it isn’t so obvious what the average power consumption is.
These types of appliances run in cycles. That is, sometimes they are running, sometimes stopped and other times starting up. Compressor motors are subject to surge current.
For the above reason, it’s often difficult to estimate average watts. The best way is to simply take last year’s energy usage from your utility bill, which will be a good estimation of what you use.
Is 50 kWh A Day A Lot?
Yes, 50 kWh is quite a lot. The average home energy usage in the US is 11000 kWh per year, which is 916kWh per month or just over 30 kWh per day.
So 50 kWh is almost 1.7 times more than the US home average.
How Many kWh Per Day Is Normal?
‘Normal’ depends heavily on the kind and size of home you have, and the location.
Homes in very hot or very cold locations will probably use more electricity, expecially if using reversible AC units. The US average is about 30 kWh per day but the usage per state can vary wildly.
Table – Compare kWh usage per day for 20 US States
Average kWh used per month
How Many Solar Panels Do I Need To Go Off-Grid?
Going off-grid means that you completely disconnect your home and its appliances from the national power grid. If you have played with the idea of doing this, then I bet you top dollar one of the first questions you have asked yourself was: How many solar panels do I need to go off-grid? The answer you will soon find, is somewhat complex and solely depends on your own home’s individual energy needs. In this article, I aim to take you through the entire solar system requirement process, and by the end of it you will know just how many photovoltaic panels you will need to take your home off-grid.
What does it mean to go Off-Grid?
Off-grid living is a characteristic of housing and lifestyle. The term “off the grid” can be associated with people that decide to disconnect their homes from the national electrical grid. Today, going off grid is still considered the ultimate path to living rough, but it does not have to be all that serious though. Off-grid living can also mean people create and utilize their own utilities, like gas, water and electricity generated from solar systems (probably the most popular option). In general, self-sustainable off grid homes tend to be popular (or rather a necessity) in locations that are more isolated from common governmental utilities like electricity. However, isolated homes are not the only ones that make use of solar panels to generate their own electricity. Off-grid living also attracts environmentally conscious, forward thinking individuals who want to reduce their ecological footprint while saving on monthly utility costs.
- In summary, taking your home off-grid means you are able to create/supply energy, drinkable water, grow food and manage waste/wastewater for yourself.
Can I Go Off-Grid with Solar Panels?
When it comes to creating and supplying your own electricity, there is possibly no greener technology more accessible and efficient than solar panels.
For the most part, going off-grid with solar panels is 100% possible. However, it is just one piece to the puzzle.
In order to maintain a healthy prolonged off the grid lifestyle, you will need some place to store all that solar energy generated by your solar panels.
And just like solar panels are the most accessible and efficient for electricity production, solar batteries/solar power stations, are the absolute best technology out there to store your off-grid solar energy.
So in essence, you can go off-grid with solar panels and some sort of storage system.
How many solar panels do I need to go off-grid?
The number of solar panels needed to go off-grid, solely depends on the following factors:
- Amount of electricity you use
- Amount of useable roof space
- Amount of direct daily sunlight
- The type of solar panel you choose
The average off-grid home usually requires about 7 Kw (or 7000 Watts) of power to rely entirely on its own energy production.
Solar panels come in various forms, shapes and sizes. Two major factors that determine the amount of solar panels you will need to go off-grid, depends on your energy requirements and the performance output of each panel.
- Panel performance is rated under standard testing conditions (STC): irradiance of 1,000 W/m 2. solar spectrum of AM 1.5 and module temperature at 25 °C.
Usually the larger the panel, the higher the panel performance.
For example, a 100-watt solar panel typically measures 47 x 21,3 x 1,4 inches. A 200-Watt solar panel measures 64 x 26 x 1,4 inches (these are rough estimates).
The bigger the framework, the more photo-voltaic cells are able to be mounted inside of it, thus more performance.
If your energy requirements were as such as the average mentioned above (7 Kw) and you were to use 200-watt solar panels, then you’d need more or less 35 panels to take your home off-grid. Or if you used 350-watt solar panels, you’d need 20 panels.
To give you an idea of how much area say 35 solar panels will take up, you will need to find the total square footage.
In the U.S, the average homes roof is about 1700 square feet.
- 35 solar panels will take up more or less 389 square feet of your homes roof space. This leaves more than enough room in case you add any extra panels to your system in the future.
To make things easier for you, we have compiled this chart to give you a basic ballpark on how many solar panels you will need depending on your situation.
Average Monthly Electric Bill
Solar System Size
Number of Panels (Based on 200W Panels)
Estimated Space Needed
How many solar panels do I need to power my home?
Solar systems are sized based on your energy usage in kilowatt-hours (kWh). But if you don’t have those numbers handy, this article offers ballpark system sizes based on familiar reference points, like square footage or number of bedrooms in your home.
When people first consider the idea of going solar, one of the very first questions that comes to mind is “how many solar panels do I need to power my home?”
Though the only accurate and reliable way to size a solar system is based on your personal energy usage, we understand not everyone has that information readily accessible. For those of you just beginning your solar research, we wanted to provide benchmark system sizes based on familiar reference points, like square footage and number of bedrooms in your home, to give you a starting point for your research.
Before we go further, we should be clear: these tables are estimates projected based on US national averages. Your energy needs may differ from what is typical of the average American home.
These tables give a benchmark to help you answer preliminary questions like how many panels can fit on your roof and whether going solar fits within your budget. If you decide to move forward, you will need to gather energy usage data and size a system around your individual needs.
Methodology
We referenced US Census data on average household energy usage, cost of electricity, and occupancy per square foot in the US to work out these projections. In all cases, the tables shown reflects how many solar panels you would need to fully power an “average” American home based on the data available to us.
Because panels come in a wide range of wattages, we’ve run the numbers for two different panel sizes: 315W and 375W. If you opt for lower-efficiency panels, you’ll need more panels in your array to hit the target production number.
Keep this in mind if space is a concern. With limited roof space, you may need to invest in more efficient panels to be able to fit the array on your roof. We’ve provided a range in our projections (from 315W to 375W) to give you a sense of how much it impacts the physical layout of the array.
How many solar panels do I need based on the square footage of my house?
Know the square footage of your home? This table cross-references on US Census data on the average household square footage against the average monthly electric usage of an American household to estimate how many panels you may need based on the size of your home.
| 250 | 0.66 kW | 2 | 3 | Shop |
| 500 | 1.33 kW | 4 | 5 | Shop |
| 750 | 1.99 kW | 6 | 7 | Shop |
| 1,000 | 2.66 kW | 8 | 9 | Shop |
| 1,250 | 3.32 kW | 9 | 11 | Shop |
| 1,500 | 3.99 kW | 11 | 13 | Shop |
| 1,750 | 4.65 kW | 13 | 15 | Shop |
| 2,000 | 5.32 kW | 15 | 17 | Shop |
| 2,250 | 5.98 kW | 16 | 19 | Shop |
| 2,500 | 6.65 kW | 18 | 22 | Shop |
| 2,750 | 7.31 kW | 20 | 24 | Shop |
| 3,000 | 7.98 kW | 22 | 26 | Shop |
| 3,250 | 8.64 kW | 24 | 28 | Shop |
| 3,500 | 9.31 kW | 25 | 30 | Shop |
| 3,750 | 9.97 kW | 27 | 32 | Shop |
| 4,000 | 10.64 kW | 29 | 34 | Shop |
| 4,250 | 11.30 kW | 31 | 36 | Shop |
| 4,500 | 11.97 kW | 32 | 38 | Shop |
| 4,750 | 12.63 kW | 34 | 41 | Shop |
| 5,000 | 13.30 kW | 36 | 43 | Shop |
How many solar panels do I need based on the number of bedrooms in my home?
If you don’t know the square footage of your house off the top of your head, we’ve also estimated average system size based on the number of bedrooms in your home.
These estimates are based on research from the NAHB (National Association of Homebuilders) which reports the average American home has 3.38 bedrooms. We’ve referenced that figure against the average monthly electric usage of an American household to produce the table below.
| 1 | 1.94 kW | 6 | 7 | Shop |
| 2 | 3.88 kW | 11 | 13 | Shop |
| 3 | 5.82 kW | 16 | 19 | Shop |
| 4 | 7.75 kW | 21 | 25 | Shop |
| 5 | 9.69 kW | 26 | 31 | Shop |
| 6 | 11.63 kW | 32 | 37 | Shop |
How many solar panels do I need to eliminate my electric bill?
Lastly, let’s assume you pay the national average rate for electricity, which is 13.3 cents/kWh. Here’s how many solar panels you would need based on your average monthly electric bill.
| 20 | 1.08 kW | 3 | 4 | Shop |
| 40 | 2.16 kW | 6 | 7 | Shop |
| 60 | 3.23 kW | 9 | 11 | Shop |
| 80 | 4.31 kW | 12 | 14 | Shop |
| 100 | 5.39 kW | 15 | 18 | Shop |
| 120 | 6.47 kW | 18 | 21 | Shop |
| 140 | 7.55 kW | 21 | 24 | Shop |
| 160 | 8.62 kW | 23 | 28 | Shop |
| 180 | 9.70 kW | 26 | 31 | Shop |
| 200 | 10.78 kW | 29 | 35 | Shop |
| 225 | 12.13 kW | 33 | 39 | Shop |
| 250 | 13.47 kW | 36 | 43 | Shop |
| 275 | 14.82 kW | 40 | 48 | Shop |
| 300 | 16.17 kW | 44 | 52 | Shop |
| 325 | 17.52 kW | 47 | 56 | Shop |
| 350 | 18.86 kW | 51 | 60 | Shop |
| 375 | 20.21 kW | 54 | 65 | Shop |
| 400 | 21.56 kW | 58 | 69 | Shop |
How many solar panels do you need based on your kWh usage?
The tables above simply give a starting point to get you in the ballpark. If you decide to move forward with your project, you’ll need to go through a more accurate sizing process based on your personal energy usage.
Energy usage is measured in kilowatt-hours (kWh), which can be found on your monthly electric bill.
Ideally, you want to base your system design off the past 12 months of electric bills, to account for peaks and valleys in usage. Bills tend to be higher during summer and winter due to the need to run A/C and heat.
The table below shows benchmark system sizes based on your average monthly energy usage. This is the most accurate way to size out your system, so if you have your energy usage data available, we’d recommend starting here.
| 100 | 0.72 kW | 2 | 3 | Shop |
| 200 | 1.43 kW | 4 | 5 | Shop |
| 300 | 2.15 kW | 6 | 7 | Shop |
| 400 | 2.87 kW | 8 | 10 | Shop |
| 500 | 3.58 kW | 10 | 12 | Shop |
| 600 | 4.30 kW | 12 | 14 | Shop |
| 700 | 5.02 kW | 14 | 16 | Shop |
| 800 | 5.73 kW | 16 | 19 | Shop |
| 900 | 6.45 kW | 18 | 21 | Shop |
| 1,000 | 7.17 kW | 20 | 23 | Shop |
| 1,200 | 8.60 kW | 23 | 28 | Shop |
| 1,400 | 10.04 kW | 27 | 32 | Shop |
| 1,600 | 11.47 kW | 31 | 37 | Shop |
| 1,800 | 12.90 kW | 35 | 41 | Shop |
| 2,000 | 14.34 kW | 39 | 46 | Shop |
| 2,250 | 16.13 kW | 44 | 52 | Shop |
| 2,500 | 17.92 kW | 48 | 57 | Shop |
| 2,750 | 19.71 kW | 53 | 63 | Shop |
| 3,000 | 21.51 kW | 58 | 69 | Shop |
To hone in on a more accurate figure, head over to our solar cost calculator and enter your ZIP code and energy usage data. We’ll provide an accurate cost and system size estimate that takes your usage and local climate into account.
Sunny Boy SMA 6.9 kW Pre-Engineered Solar Panel Kit w/ Secure Power Supply
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SMA Sunny Boy US Series with Secure Power Supply
- Daytime Power During Blackouts
- The Sunny Boy SP series of inverters have the Secure Power Supply feature which provides daytime power during grid outages without batteries. The world’s first Secure Power Supply now delivers up to 2,000 Watts, (when connected to a customer supplied 120 VAC outlet) of opportunity power when the grid goes down and the sun is shining. Its transformerless design means high efficiency and reduced weight. Multiple MPP trackers and OptiTrac™ Global Peak mitigate the effect of shade and allow for installation at challenging sites. As the world leader of solar inverter technology and manufacturing, SMA stands behind the reliability of the Sunny Boy line for the long term and takes pride in providing customer service that is second to none.
Only:
Optional: Roof Mounting Ground Mountingnbsp Rapid Shut Down if needed. 1 for each panel)
P/N sma-Mi-345-6900. 6.9 kW SMA Sunny Boy Solar Kit with US Made Mission Solar Panels
- 20. 345W Mission Solar Panels Black Frame Mono MSE345SX5T
- 1. SMA, Sunny BoySB-6000-US 1-Ph Grid Tied Inverter, 5000W. Built in Ethernet/WLAN
- PV Wire, 10AWG, UL4703 with H4, 600VDC as Required to Edge of Array
- 4. Arlington, Strain Relief, Cord Grip, 1-Hole, 1/2, with locknut
- 1. AC Disconnect, NEMA 3R, 30A, 240VAC, 2-Pole Unfused
- 1. Multi-Contact MC4 Unlocking Tool
- 1. Line Drawing; Full Instructive Three-Line Diagram of Entire DC Circuit, as Well as AC Lines to Your Metered Service Entrance.
- Smart Connected monitoring platform included. The monitoring platform software is included but requires Wi-Fi connnection to the inverter.
American Made Technology, Easy to Order, Fast Delivery, Simplified Installation.
The Sunny Boy is a transformerless solar inverter which converts the direct current of a solar array into grid-compliant alternating current and feeds it into the utility grid. The Sunny Boy is a multi-string inverter that has two input areas, A and B, each with its own MPP tracker. This continually determines the maximum power point and controls the voltage on the solar modules accordingly. The two separate MPP trackers make it possible to connect different solar strings to input areas A and B. The solar strings may vary in the number of solar modules, their orientation to the sun and shading. We strongly recommend tasks described in the installation of the solar system may only be performed by qualified persons. The qualified person must have the following skills: knowledge of how an inverter works and is operated, training in how to deal with the dangers and risks associated with installing and using electrical devices and knowledge of and adherence to the solar plans and installation instructions provided and all safety precautions.
Installation and Technical Documents
The SMA 6.9 kW System Solution w/ Mission Mono Panels US Made
Production = 931 W Per Month Assumptions: 345 Watt STC Panel Rating [Factory Rating] @ 5 Sun Hours (Average).
SMA with Secure Power Supply
NEC 2014 690.12 specifies a requirement for a Rapid shutdown of solar systems installed on buildings [Building Installed Only].
SMA Sunny Boy SP series inverter comes standard with advanced features like it’s off-grid capabilities and full grid management functionality. Solar systems are required by code to disconnect from the electrical grid when the power goes out. Traditionally, that meant your system would deliver zero power to your home, but not anymore. SMA has pioneered the Secure Power Supply (SPS), which will continue to deliver power from your solar system to your outlet when the sun is shining, even when the power goes out. A dedicated wall outlet is wired directly to the inverter, providing security and ensuring power is available when it’s needed most. SPS delivers up to 2,000 Watts of opportunity power when the grid goes down and the sun is shining.
Secure Power Supply Operation
You can connect an external outlet and a switch to the inverter in order to activate the outlet. In case of a grid failure, the outlet supplies a load with current from the solar system. When the outlet is activated via the switch, the load is supplied with current from the solar system. The inverter automatically regulates the energy supply of the outlet depending on the solar irradiation on the solar system. When the outlet is activated and a load is supplied with current from the solar system, the inverter is disconnected from the utility grid and does not feed into the utility grid.
Power = Savings on Your Energy Bill.
The Sunny Boy’s multiple independent input channels, each with SMA’s OptiTrac™ Global Peak, mean hundreds of stringing configurations for flexible system design while solving the challenges of complex roofs and shading. The SMA Sunny Boy SP inverter series feature simplified design which means reduced costs for residential solar installations. The Sunny Boy US features an integrated DC disconnect, simplifying the installation and providing a safe system operation.
SMA California Rule 21 compliance is fast and easy! Click on Videos Tab ⇑ above What’s On the Truck to learn more.
CA Rule 21 currently governs CA HI Rule 14H utility interconnection for all net energy metering for all projects permitted and approved for interconnection. The change was designed to create a standard for inverters more capable of dealing with a volatile utility grid. Why is this needed? Utility companies are facing higher penetration rates of solar and in some cases are saturated and needed an additional low/high frequency ride-through. By using so called Smart inverters the functionality keeps grid voltage from oscillating or acts like a shock absorber intended result is automatic stabilization of utiltiy grid voltage.
Personal Technical Advisor
Line drawing questions or just stuck? No worries we have your back and will be here to help whenever you have questions about your purchased Kit. For orders larger than 2,000.00 a Technical Sales Team Group Captain will be assigned your account. Your Technical Advisors job is to coordinate all parts and pieces of your order and to work with you throughout the process. This support helps because we will be providing you with a single contact point to call with your questions. Your technical support contact does not replace the maufactures warranty technical support. DIY means you accept the responsiblity of reading and following the line diagram and other installation documents prior to tackling the installation.
NOTE: For detail support after installation customer must be willing or have the ability to connect to the SMA Smart Connected monitoring platform. The monitoring platform software is free but requires Wi-Fi connnection to the inverter.
Mission Solar Panels 19.1% Panel Efficiency
Blue Pacific Solar® SMA America Kit is featured with Mission panels. Mission Solar Energy, proudly assembled in the USA, is headquartered in San Antonio, TX with module facilities onsite. Mission Solar hardworking team calls Texas home and is devoted to producing high quality solar products. Our supply chain includes local and domestic vendors. 25 Year Warranty, UL Listed.
Need Help With Permit Documents?
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Solar Permit Document Service
- Blue Pacific Solar® permit document service is offered as a value added service for our customers only who purchase our grid-tied or off-grid packages of 18 panels [Minimum] or more. The building permit document permitting service service is available for most states to help you get through your local jurisdiction building permit process. Our team of professional designers can provide the documents, blueprints and expertise needed to work with any building department nationwide.
System Qualifies. 26% Federal Solar Tax Credit- State Tax Credits May also Apply
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Federal Solar Tax Credit
- The federal solar tax credit, also known as the investment tax credit (ITC), allows a taxpayer to claim a credit of 26 percent for a qualified system located in the USA and that is owned and used as a residence by the taxpayer.
Options Accessories
Grid-Tie, Off-grid DIY Solar Backup Power Self-Consumption Installation Packages
The do-it-yourself (DIY) craze is hardly crazy when one considers the mind-boggling cost savings resulting from this trend nationwide. In fact, many people wouldn’t call it a trend at all, merely a return to the practical know-how of yesteryear when people simply had to do it themselves and took great pride in their handiwork! Yet few DIY projects are as cost-saving and investment-rich as the installation of a solar system.
The era of solar energy, as many would say, is upon us. From astounding new solar products like AC coupled backup systems and high efficient microinverters to banks of solar panels that provide electricity to run our homes and, eventually, even our cities, the solar revolution may well have begun in earnest. Yet too most people, how solar actually works is a mystery. How do these panels convert sunlight into energy that homeowners can use to power their appliances and their homes, a practice that ultimately protects the environment and leads to cheaper utility bills and economic freedom?
Photon to Electron
So how does a seemingly simple looking panel harness sunlight and transform it into electricity? Solar panels contain photovoltaic cells. These cells are where the conversion from light to electricity takes place. The cells must be made of a material like silicon or a similar single cell semi-conducting material. As light enters the cells, the semi-conductor pulls the energy in the form of electrons from it and allows them to flow through the material. In essence, this flow is actually a current. While the absorption of the light into the cell is enough to free electrons, the cells also contain an electric field that can steer the electrons where they need to go. The current is then steered to the bottom of the panel where it can then be collected and drawn for use externally.
Atomically Speaking
Most people don’t think in terms of particles, but light actually hits the PV (photovoltaic) cells as photons. As each photon hits the PV cell, it gives up an electron. While this is putting it somewhat simplistically, this is, indeed, the moment of conversion. The freed electron is absorbed by the silicon where it flows with other electrons into current; hence, electricity is born. Some scientists would say that the real tricky part is enhancing the cell with an electrical field to get all these electrons in line to flow as a current in the required direction: enter silicon.
The Role of the Semiconductor
Silicon is popularly used as the solar cell’s semiconductor. Yet it must do more than simply absorb photons; it has to employ an electrical field and get their current moving along. over, it must be fashioned with impurities, because pure silicon will not do the job alone. Phosphorous and boron are added in a process referred to as doping and together these elements in their atomic interaction create the electrical field needed to move the electrons in the prescribed current they need to flow.
From Panel to Refrigerator
After the photons are transformed into electricity, the panels direct this energy to power the home. Some homes, those independent of the utility grid, must rely on battery storage to store energy, yet they may also have to rely on backup generators when there is too much demand on the size of the system. Many people use solar in tandem with the utility companies so that they have a convenient back-up during fluctuating periods of energy. This net metering partnership is a bit involved, but it has also been evolving to become more effective as more and more people choose solar to provide the bulk of electricity to power their homes.
Solar Panels
It goes without saying that solar panels are essential for a solar power system. Actually, what you will probably need is known as a solar array. That is because each panel generates a small amount of electricity. The number of panels included in your solar array depends on how much power you need to generate. PV photovoltaic modules, often referred to as solar panels, convert light energy into a direct electrical current (DC). As solid-state devices, solar panels have no moving parts and are extremely reliable and durable compared to any other generator electronic technology. While solar panels have become somewhat commoditized in recent years, there are important differences in form, quality and performance that can impact both installation time and long-term system performance. Our web pages presents a selection of high-quality polycrystalline and monocrystalline solar panels with a variety of features and cheap price points to suite virtually any homeowners project.
Solar panels come in two types; monocrystalline and polycrystalline. Where home or cabin owner wants their solar installation to be grid tied, off-grid or emergency solar backup each of those systems starts with a solar panel selection. Monocrystalline solar panels are generally higher efficiency, but they tend to derate faster in hotter conditions. Polycrystalline are sometimes considered a better choice for warmer climates, but the truth is that either panel type is so similar the differences are relatively not worth comparing.
What is the Best Solar Panel to Choose? The output power, voltage and current profile of the solar panels will dictate the number of panels needed and what inverters or charge controllers can be used. Small off-grid home or cabin kits often require 12 VDC output panels to directly charge batteries and/or operate DC loads. Larger solar panels with output voltages ranging from 24 to 50 VDC are more commonly used in grid-tie home systems where a high DC voltage is required to operate the inverter. If you have the roof or ground space with limited shading issues on your property, the larger solar panels may provide a better investment since the cost per watt is cheaper than smaller PV (Photovoltaic) panels.
Connect to the Grid or Not, or Both; That is the Question
PV (photovoltaic) systems can be grouped into two categories, off-grid and grid tied. In off-grid systems the energy produced by the solar panels must match the daily demand of the home or cabin, and the power is stored in a set of batteries. With grid-tie solar systems, the local utility company functions essentially as the battery bank during the night. In America, most solar systems are grid-tied with all of the excess electricity generated being fed back to the utility grid hence the term NET metering.
When you hear the term off-grid which is synonymous with stand alone systems, you may generate a picture in your mind of rustic pioneer-type living in a cabin with few modern conveniences. In fact, this is not necessarily the case. While it is true that off-grid solar power is usually not sufficient to power an electric heating and cooling system unless you just won the Lotto or work on wall street, nearly all other appliances can be adequately powered with a properly configured off-grid system. You simply start with a daily energy budget and match the right components to meet your power demands. Check out our off-grid living page for some great information to help you plan the right system for you.
Solar panel mechanical characteristics such as dimensions, frame profile, and static load rating, as well as grounding and mounting locations will need to be understood when designing your home solar grid tied or off-grid system. Frame and back sheet color may also come into play for residential DIY customers. Black frame solar panels are very popular because the aesthetics of the panel blend very well with many roof applications.
Solar Mounting Structures, Racks and Trackers
Solar mounts and solar trackers are nearly as important as the panels themselves. Solar mounts provide the stability your panels require to remain in place. Solar trackers allow you to orient your panels automatically to take maximum advantage of the sun’s rays. The IronRidge, SnapNrack and UniRack roof and ground mount module racking we sell were developed by teams of engineers working with installers in the field to ensure quick, efficient installation.
Outback, Magnum Energy, Enphase and SMA; AC Pure Sine Wave Power Inverters
The electrical current generated by your solar array will be direct current, or DC electricity. Most electrical appliances run on alternating current, or AC electricity. A power inverter converts the DC power of your solar array into AC power that your appliances can actually use. DC electricity travels in only one direction but AC electricity alternates back and forth. Without a power inverter, you will be forced to rewire your home and to purchase expensive DC powered appliances over lower cost mass-produced appliances made for the conventional home power source. In some cases, DC powered appliances will not be available and you will have to do without certain appliances. If you intend to be off-grid, you should consider propane to power things like stoves and refrigerators. Heat with a pellet or wood burning stove but make sure they are highly efficient modules that use less fuel.
Deep Cycle Batteries, Battery Monitor and Solar Charge Controllers
Without a deep cycle battery system, you will be unable to store the electricity that your solar power unit generates. This means basically that you will only have power when the sun is shining. Deep cycle batteries are specially configured to be charged and discharged frequently with a high demand system like a solar power system. The battery monitor provides a visual gauge of the electricity generated and stored by your solar power system, while the solar charge controller manages the process of charging your deep cycle batteries making sure they receive just the right amount of power but controlled and regulated throughout the day.
Battery Cables, PV AWG Wire / MC4 Connectors, Combiner Boxes, AC Disconnects; Electrical Distribution Balance-of-System Accessories.
These small items are minor but essential for making your solar panel kit work. You will need, among other items a solar combiner box, AC breaker panel, DC Breaker box, DC breakers, battery cables, remote temperature sensor, AC and DC wire and solar power cables. Cables and connectors on the solar panels we carry above 80 watts are generally manufactured with PV wire into the panel junction box that are listed to UL 1703. This can save time during installation. The modules with MC4 cable connectors are fully waterproof when connected, touch protected and designed for up to 600 volts DC and 30 Amps. It is important to keep in mind that PV cables cannot be safely disconnected under load. All of our grid tied and off-grid output cables are made with UV resistant wire that is Listed to UL 854. You may also wish to add other solar accessories. Blue Pacific Solar® also carries a variety of cable adapters that enable use of optimizers or microinverters that may not be available with the same connector type as the module chosen for the job.
Home Emergency Backup Generator
If you are worried about utility blackouts, take at look at Blue Pacific Solar® off-grid power generators and pre-wired, pre-engineered power center equipment. A backup solar generator can provide you with peace of mind during utility power outages and blackout or other weather related emergencies. With a grid-tie system when the utility provided power goes down, your solar power system is nonfunctional, you will be literally in the dark without a backup generator or battery bank to power essential loads. Your solar back up generator will automatically switch over to your battery bank and so that it takes over immediately in the event of a blackout when the grid goes down. Our solar generators are designed in compact kits that work by having stand-by batteries connected to an AC inverter.
AC Coupled Battery Backup Systems
Until very recently there were few options available to homeowner with grid-tied systems to utilize the energy from their solar panels when there is a utility blackout. On our backup solar page we offer a number of stand alone AC coupled emergency backup kits that use your existing solar system with our AC coupled system to provide power to your home in the event the utility goes down. The AC coupled system will take the energy from your solar panels and use it to charge a battery bank that will in turn power your essential loads. Additionally, SMA Sunny Boy 3000TL-US / 4000TL-US / 5000TL-US is a new innovative design and the next step in performance for UL certified inverters. A unique feature provides daytime power from your solar panels even in the event of a grid outage, without the need for batteries.
DIY (Do-it-yourself) off-grid / grid-tie solar panel kits and pre-wired home backup power packages. Solar can recharge your life while creating jobs in a new economy. Everyday Blue Pacific Solar® Technical Sales Consultants are hard at work engineering new ways to help homeowners everywhere; see what the sun’s free energy can do for their life.
The Ultimate Guide To Solar Panel Calculation
Solar power is a sustainable energy solution, and the goal is to make the most out of it and reduce dependence on the electrical grid. While switching to solar energy seems easy, calculating the number of solar power panels required can be challenging.
During solar panel calculation, there are a variety of factors that you need to keep in mind. These include geographic location, home energy usage, number of sun’s peak hours, etc.
If you live in a location that receives few peak hours of sunlight, consider purchasing Jackery SolarSaga Solar Panels with a high conversion rate. These solar panels can convert most solar energy to usable electricity.
But before you purchase solar panels for your power needs, read this guide. This guide will help you calculate the load wattage, power output, energy usage, backup time, etc., of the solar panels, so you make the best choice.
What Is a Solar Panel?
A solar panel (also called a photovoltaic cell or PV panel) is a device that converts the sun’s energy into electricity. The energy generated is then used to charge power stations, which power all your electrical appliances.
Solar panels consist of individual solar cells composed of silicon, phosphorus, and boron. When photons from the sun’s energy strike the surface of a solar panel, they knock out the electrons to create a directional current.
DC current directly transfers from the solar panels to the power station, where the inverter converts it to AC electricity. Using the combination of power stations and solar panels, you can quickly charge electrical appliances at home or during outdoor adventures when you are away from the electrical grid.
The Benefits of a Solar Panel
Solar panels are a clean and renewable energy source for homeowners and outdoor enthusiasts. Below are the benefits of using a solar panel and power station to charge your appliances.
- Clean Green Energy:Solar panels do not emit toxic fumes while converting the sun’s energy into electricity. Hence, they are a clean, green energy source that reduces your carbon footprint.
- Zero Maintenance:Solar power panels are easy to clean and maintain. All you need to do is wipe the dust off with a soft, clean cloth to improve its efficiency.
- Safe:Unlike gas generators, solar panels do not require coal or gas to generate electricity. Hence, they are pretty safe for indoor use.
- Reduces High Electricity Bills:You can power all your home appliances with solar panels and a portable power station. Thus, renewable energy helps reduce high electricity bills and save money.
- Eco-friendly:Solar panels reduce the emission of greenhouse gases like carbon dioxide, nitrogen oxides, sulfur oxides, etc., into the atmosphere, making them an environment-friendly power solution.
Solar Panel Calculation
There is no single accurate answer to how many solar panels a home needs. Every home is different, and so are its power needs. Using a solar panel calculator and understanding various variables gives an accurate estimate of how many panels you’ll require. Some essential factors you’ll need to consider are load wattage, energy usage, solar panel backup time, efficiency, etc. Let us discuss each aspect in detail.
Solar Panel Output Calculation
Generally, solar panels produce a few hundred watts to 400 watts per hour. However, there are several external variables that affect the actual output of the panels.
Some important factors include how many hours of sunlight the solar panels receive, your location, and how many watts your panels can produce in an hour.
To help you understand better, here is the mathematical solar panel calculation of daily watt-hours.
Daily watt hours = Average hours of sunlight × solar panel watts × 85%.
(As not all the sunlight is converted into electricity, we tested to determine that the Jackery solar panels are 85% efficient.)
Suppose you live in an area that receives 4 hours of peak sunlight, and your panel has a 200-watt rating. In this case, the solar panel output will be:
Daily watt hours = 4 × 200 × 0.85 = 680Wh.
That means one solar panel with a 200-watt capacity can produce around 680 Wh, depending on its efficiency.
For instance, if you purchase Jackery SolarSaga 200W Solar Panels, you can enjoy a high conversion rate and efficiency. Along with the portable power station, these solar panels can convert sunlight into electricity and power appliances.
Load Wattage Calculation
The load wattage is the next important thing you’ll need to keep in mind while buying a solar panel system. In simple words, load wattage involves analyzing your power requirements by understanding how many appliances you wish to charge and for how much time.
To calculate the total load wattage of the electrical appliances, you need to multiply the power used by each device by the number of usage hours per day. This will give you the total kWh per day of one appliance.
For instance, if you wish to run a refrigerator for 6 hours and it consumes 300 watts per hour, here is how to calculate its load wattage.
Load Wattage = 300 × 6 = 1800 Wh.
Similarly, you can calculate the load of all other home appliances. Add them up, and you will get the total power you need for one day.
Energy Usage Calculation
The next crucial step for solar panel calculation is to determine your home’s average electricity consumption and energy usage. The amount of energy an appliance uses in an hour is termed energy usage.
To get an estimated energy usage value, you need to figure out daily kWh usage, peak sun’s hours, etc.
Here is how you can calculate it:
Step 1: Calculate the kWh usage: First, you need to gather the kilowatt-hour usage from your electricity bills. Next, determine the average monthly kWh by adding 12 months of kWh usage and dividing it by 12. Divide the resulting number by 30 to calculate daily kWh usage.
Step 2: Determine peak sun hours: Note down the peak sun hours you receive. Remember, not every location gets the same amount or intensity of sunlight. To make the most of solar power, calculate the average sun hours you receive and move to the third step.
Step 3: Calculate Solar System Size: The last step is to determine the size or capacity of the solar system you’ll need to power appliances. You can simply divide the daily kWh by the average sun hours. Then, multiply the result by the panel’s efficiency to get an estimated solar system size.
Note: Always use highly efficient solar panels with a power station to charge appliances. Instead of connecting hundreds of solar panels, you can purchase a combination of powerful power stations with high battery capacity and connect them with solar panels.
Refer to the table to determine the energy needs of different appliances.
Kitchen Appliances
Living Room Appliances
Outdoor Appliances
Coffee Machine
Video Game Console
Electric Blanket
Electric Kettle
LCD Monitor
Electric Oven
Circular Saw
Solar Panel Backup Time Calculation
The backup time of the inverter or solar power station determines how long it can provide power during outdoor adventures or power outages. The backup time of a solar energy system depends on the solar battery size and charge consumed by the appliance.
The battery capacity is generally measured in AH (ampere-hour). The most common battery type is 12V, which provides 80% efficiency. The more the solar panel backup time, the longer you can run your devices.
Here is how you can easily calculate it:
Battery Backup Time = (Battery AH × 12V × battery efficiency) ÷ Total power consumption.
Suppose you are running an appliance that consumes 100W of energy. In this case, the backup time will be: (100 AH × 12 V × 0.8) ÷ 100 watts = 9.6 hours.
Hence, you can run the appliance for 9.6 hours with a 100 AH battery capacity solar power system.
Solar Panel Cost Calculation
With the increasing popularity of solar panel systems, many homeowners are planning to harness solar energy. However, the cost associated with solar panels before switching to renewable energy is worth noting.
The main factors that affect the overall cost of solar panels include the type of panels you wish to install. For instance, if you’re planning to install monocrystalline solar panels that are highly efficient, you’ll need to pay a few extra bucks.
Other factors influencing solar panel calculation include size, conversation rate, and other relevant features of solar power panels.
Alternatively, you can use the solar panel cost calculator to determine the overall expenses.
Solar Panel Paycheck Period Calculation
The solar panel payback period is the estimation of the time it takes for the solar panel system to generate enough energy savings so you can offset the initial investment.
The simple formula to calculate the payback period is the total cost of the system divided by the average yearly energy savings.
Payback Period = Total cost of solar panel system ÷ Average yearly energy savings.
Suppose you’ve purchased a solar system of 20,000 that helps you to reduce your electricity bills by 70 per month.
In this case, the average yearly energy savings will be 70 × 12 = 840.
Payback period = 20,000 ÷ 840 = 24 years.
Hence, solar panel systems will take 24 years to completely offset the initial investment.
Solar Panel Efficiency Calculation
Solar panel efficiency, in simple words, represents the amount of sunlight a solar panel can convert into usable electricity. It is calculated by dividing the amount of electricity produced by the solar panel by the amount of the sun that strikes the solar panel.
Here is the mathematical representation of the solar panel efficiency.
Efficiency (%) = [(Pmax ÷ Area) ÷ 1000] × 100%.
Pmax = Maximum solar panel power (measured in watts).
Area = Length × Width of solar panels (measured in sq. M).
1000 = Conversion factor to convert power output per unit area from watts per sq. M to percent.
Suppose you have a solar panel with a maximum power output of 200W and a surface area of 1.6 m2. The efficiency of solar panels would be:
Efficiency = [(200 W ÷ 1.6 m2) ÷ 1000] × 100% = 12.5%.
In this case, the solar panel efficiency is 12.5%. That said, it can convert 12.5% of the sunlight that hits the panels to electricity.
Surface Color
Fraction of Incident Radiation Absorbed