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Generator Sizing Guide For Off-Grid Solar Systems. Solar generator 5kw

Generator Sizing Guide For Off-Grid Solar Systems. Solar generator 5kw

    Generator Sizing Guide For Off-Grid Solar Systems

    Most off-grid solar systems are paired with a generator. Without utility power as a fallback, off-grid setups need a backup plan in case their solar system can’t produce enough to meet the property’s needs.

    Gas generators are used in off-grid systems as a backup charging source to recharge the battery bank when solar can’t keep up with demand. They are also used for backup power in case equipment fails and the inverter system needs to be bypassed.

    generator, sizing, guide, off-grid

    Here’s our advice on how to pick a generator for your off-grid solar system.

    Generator Sizing

    As a general rule, the generator should be around 2 times the size of the inverter’s continuous output. For example, a 4,000-watt inverter should be paired with an 8,000-watt generator.

    This is because the generator needs to charge batteries while still powering the loads (appliances using energy). If the loads total 4,000 watts, and the charger is 60 amps at 48 volts, that totals around 7kW of continuous power:

    60a x 48v = 2,880 watts 4,000 watts = 6,880 watts

    8kW would make sense as a minimum generator size to power the loads and have enough power to charge the battery bank as well.

    It’s a good idea to round up slightly to give some headroom for the generator, especially at higher elevations where your generator is going to lose some of its power. Engines can lose around 3% of their power for every 1,000’ increase in altitude. Make sure you account for this if your system will be installed at a high elevation.

    Can I Use a Larger Generator?

    A larger generator can be beneficial if you have large loads like an air conditioner or a welder that will only be used when the generator is running.

    We frequently sell 12kW and 14kW Kohler generators with our off-grid systems using a 4000w inverter. A larger generator is going to burn more fuel, but otherwise will work fine.

    Can I Use a Smaller Generator?

    Smaller generators will still work, but it typically requires adjusting the settings to limit the battery charger’s output. Most battery chargers allow you to adjust the AC input amperage and charge rate.

    You will need to match the generator’s voltage with the inverter. For example, 120Vac generators should be paired with 120Vac inverter/chargers, while 120/240Vac generators need an inverter that outputs 120/240Vac.

    In the rare case that you are using a three-phase generator or inverter, the same rules apply: the generator’s voltage would need to match the inverter.

    There is one exception we are aware of. Magnum PAE inverters are 120/240Vac but can handle a 120Vac input, provided you turn down the charge rate to 50% or lower, and adjust the AC input amps to match the size of the generator. This is useful if you need an inverter that can output 120/240Vac but are working with a smaller generator.

    Generator Fuel Type (Natural Gas, Propane, Diesel)

    Most standby home generators work on natural gas, propane or diesel. Diesel generators tend to be much more fuel efficient and longer lasting, but the initial cost can be 2-3 times more than a natural gas or propane alternative.

    The Kohler 12kW 14kW generators we sell can work with either natural gas or propane. Off-grid customers typically use propane instead of natural gas, but these models can be configured to work with either fuel type.

    Other Considerations


    Most generators don’t have a warranty that covers off-grid or prime power applications. Check the generator warranty closely to be sure it can be used off the grid.

    Kohler’s 12RES and 14RESA generators are both warrantied for 18 months / 1000 hours of off-grid use (whichever comes first).

    If you need more power, dual 14RESA generators can be combined in parallel with the Kohler Powersync module for 28 kW of output.

    2-wire start

    Off-grid generators paired with solar power systems need 2-wire start capability to allow the automatic generator start (AGS) function to work. When your batteries drop below a certain voltage, the AGS kicks in to turn on the generator and recharge your battery bank.

    Note that 2-wire start is different than electric start. Some generators will have a button for electric start/stop, but they can’t be controlled by a 2-wire signal, which means the inverter can’t communicate with the generator to trigger the AGS mechanism.

    The Kohler 12RES and 14RESA are both capable of two-wire start.

    1800 RPM vs. 3600 RPM

    Most generators operate at one of two engine speeds: 1800 or 3600 RPM.

    The difference is based on engine design and the alternator being used. 1800 RPM generators are generally considered superior because they are more fuel-efficient, but they cost quite a bit more up front. 3600 RPM generators tend to be cheaper but less efficient.

    The Kohler 12kW and 14kW generators we sell are 3600 RPM. They are very durable, reliable and more cost-effective for typical off-grid applications. Kohler doesn’t make any 1800 RPM generators smaller than 24kW, although there may be options from other manufacturers. Be sure to do your research and read reviews to learn about the company and make sure you are getting a quality product.


    When searching for a generator to support your off-grid solar system, keep a few things in mind:

    • Generator output should be 2x your inverter’s output
    • Match generator voltage to inverter voltage
    • Generator must be warrantied for off-grid use
    • 2-wire start is mandatory to work automatically with solar system
    • 3600 RPM generators are more cost-effective, while 1800 RPM generators cost more up front but last longer and are more efficient

    For more help moving off the grid, check out our Solar Battery Guide, which explains how to size and select a battery bank to adequately support your energy needs off the grid.

    How many solar panels can a 5kw solar inverter off grid handle?

    A 5kw solar inverter is widely used for 5kW solar power system, it should easily offset a typical home’s electricity usage.

    However, most users installing solar these days tend to install systems larger than 5kW as this provides better bang for buck – 6KW 6.6kW systems are now considered entry level.

    5kW solar systems are also the minimum system size you should be considering if you’re looking to add batteries to your system in the future – again, most who intend installing batteries option for larger systems.

    How many solar panels for 5KW solar power system?

    To make up a 5kW solar system, you need 12 units half cell solar panels, assuming you use 450 watt solar panels – that will actually give you 5.4kW.

    Each solar panel will be about 1.91 metres x 1.13 metre, so you’ll need at least 26m² of roof space.

    To give you a feel for how big 26m² is, this picture may help:

    Choose a 5kw solar inverter

    You can choose high PV input voltage range(120Vdc-450Vdc) 5kw solar inverter, transformerless design provides reliable power conversion in compact size. Besides, it’s worry-free to start up motor-type loads such as refrigerators, motors, pumps, compressors and laser printers as well as electronic loads like TV’s, Computers, power tool and battery chargers.

    How much electricity will generate?

    First we should look at what the available “average sunlight” should do for a solar system. This graph shows the expected output on an average day for a north facing, unshaded solar panel system.

    While this is a fairly broad generalisation, it is fairly typical of what you could expect to see at an initial glance what a solar system might produce. For instance, on an average sunny day at 10am in summer an average 5kW solar system would likely be producing up towards 3.5kW to 4kW but in winter you might only expect between 2kW and 3kW.

    There are again many factors to take into account to accurately predict how much power your solar system should make each day. But there is also a VERY simple formula to give you a rough idea.

    Daily Average Production = Solar Array Size x 4

    So a 5kW solar system should on average produce around 20kWh per day. You will likely see much more power produced during great solar days in summer, probably up to 30kWh and much less power produced during a cloudy winter day maybe lower than 10kWh. But over the year it should average out to around 20kWh. You don’t need to be out there with a pen writing all this down, but if you would like to do an occasional check just before dark, check the daily total. Divide by 4 and you should have a number pretty close to the size of your solar array.

    How many AC can 5kW solar inverter run?

    The 5kW solar system is for big houses, offices and commercial shops. 5kW solar power system is the preferred choice for customers having frequent power cuts in home, commercial shops etc. It comes with 5kw solar inverter off grid. It can run 2ton AC with 2 Fan, 8 LED lights and 1 Fridge easily.

    If you are not exporting all of the energy and assuming you’ve paid a reasonable price for a 5kW solar system, then you should see a payback period of less than 5 years – so a fairly Rapid payback timeframe.

    How Much Power Does a 5kW Solar System Produce?

    So you got yourself a 5kw solar system but don’t know what exactly it can power. Don’t worry, it isn’t a straightforwards answer.

    But lucky for you, we’re here to help you answer that question while giving you some tips on solar systems of that size.

    Join us as we break down how much power a 5kw solar produce.

    How Much Does a 5kW Solar System Produce?

    Whether we want to know how much a 10kw solar system produces. or the smaller 5kw system, all systems use the same approach.

    However, certain factors prevent a solar system from reaching its full potential, and it’s important we briefly discuss them.

    Factors Affecting a 5kW Solar System Output

    Solar systems never reach their full solar output because of various factors.

    One of these is the shading and weather in your area.

    If you have your solar system on the roof of your home but happen to have tall trees obstructing the solar panel’s visibility from the sun, it affects your solar efficiency.

    Weather conditions also affect the solar system’s performance as heavy rain and snowfall can damage the equipment.

    Irradiance also plays a role in reducing solar efficiency.

    If you’re in an area that doesn’t receive much sunlight, you need to rely heavily on solar generators and batteries to obtain the bare minimum.

    The other factor that affects the solar system’s output is the tilt angle of the solar panels.

    Ensuring that your solar panels are obtaining optimum performance means that they need to be facing south. You also want to ensure they are at an angle between 30 and 45 degrees.

    This shouldn’t be a problem as your solar installation team will suggest orientations based on where you reside and where you want your solar system installed.

    If it’s on your roof, we suggest maintaining your roof before asking for a quote.

    Another minor factor is choosing between the different types of solar panels.

    A single 200W solar panel that falls under the monocrystalline category will be more efficient than a polycrystalline one with the same wattage.

    How Much Power Does a 5kW Solar System Produce Per Day?

    To calculate how much power a 5kw solar system produces per day, we have two approaches. Using national average amounts and Ohm’s law.

    The former is great when it comes to calculating how much a 75kW solar system produces or any solar system measured in kilowatts.

    The latter is perfect for smaller solar systems using a few solar panels.

    Using Averages to Calculate the Output

    When we speak about averages, we’re referring to values like the national daily power usage in the states. This is around 30kWh for the average American household.

    The first step of the average method is taking this value and dividing it by the solar irradiance in your area.

    To determine this value, you want to refer to an online solar map that shows you how many sun hours your area receives each day.

    For this example, let’s say you reside in an area that receives around 6 sun hours daily. We want to take the national daily power usage and divide it by the 6 sun hours.

    This shows us, on average, how much power in kWh is needed in your household.

    So taking the 30kWh average and dividing it by 6 sun hours, your house would need around 5KW of power per day.

    generator, sizing, guide, off-grid

    Whether we want to know how much a 15kw solar system produces. or the system we’re working with, each consists of solar panels within the system.

    The average solar panel produces around 250W of power when under peak conditions.

    However, as mentioned earlier, certain factors affect the panels from reaching their peak solar output.

    The power produced by solar panels is DC, however, our homes require AC power to provide energy to our appliances.

    Solar Panels go through a conversion process, and this leads to a loss of around 80% of the power. In a 5KW system, we have around 6.25KW of DC power before the loss.

    generator, sizing, guide, off-grid

    This same statistic applies to all solar systems. So, if we want to find out how much power a 45KW solar system produces. obtaining the DC power would be dividing the amount by 80%.

    This gives us 54KW of DC power. But for now, we’re going to FOCUS on the 5KW solar system.

    Before we can figure out how much power is produced from a 5KW solar system, we need to figure out how many solar panels we need.

    How Many Solar Panels Are Needed?

    Figuring out the number of solar panels needed in a 5KW solar system is a simple process.

    You take the DC amount from earlier and divide it by the solar panel’s rating that you are wanting to purchase.

    Let’s say we want our solar system to make use of 300W solar panels.

    Using our value of 6.25KW, we would need around 21 solar panels, giving us a solar system containing 21 300W solar panels.

    For a more even number of solar panels, you can use the 250W ones. This gives us an array of 25 solar panels.

    If we wanted to figure out how much power an 8kW solar system produces. the same steps apply. We should always determine the number of solar panels needed.

    How Many KWH Does a 5KW Solar System Produce?

    Using the values we obtained from our calculations, we can put everything together.

    In our 5kW solar system that’s located in an area receiving around 6 peak sun hours, for 365 days, we get an annual amount of 10,950kWh each year.

    Dividing this by 12, we get the monthly amount that the 5kW solar system supplies. This is around 912kWh.

    Going a step further, getting the daily amount equates to 30KWH of energy per day.

    Using Ohm’s Law

    This approach is best suited for smaller systems.

    You can figure out how much electricity a 4kw solar system produces. as well as a 5KW one, but you’re going to need bigger and more powerful equipment for the measurements.

    Ohm’s law states that the voltage of our solar system is equivalent to the multiplication of the current and the resistance.

    The wattage of a system is achieved by multiplying the current and the voltage.

    We’re going to stick with our 300W solar panels in our 5kW system while working with Ohm’s Law.

    Solar panels can reach their peak when wired up to a certain resistive load.

    This value should be significantly higher than the solar panel’s rating, but since we’re working with a system, it should be above the system’s rating.

    For this solar system, you want to use a wire wound power resistor measuring slightly above 5kW. Resistors in this region can have a resistance of anywhere between 1 ohm to 100 kOhm.

    If your solar system is set up correctly, using a volt meter across the resistor in your system in direct sunlight, the voltage shouldn’t be over 100.

    Calculating the current requires us to take the voltage read from the volt meter and divide it by the resistor’s measurement.

    These values are all interchangeable. In other words, you can calculate the voltage, current, and resistance in a system with Ohm’s law.

    This method is more challenging than using averages, but you end up with a more accurate value. However, the values of the two methods should be close, and if not, in the same region.

    What Can a 5kW Solar System Run?

    A system of this magnitude can power almost anything in a standard 4-bedroom American home.

    Different appliances require different amounts of power to operate. Needing to power a TV requires much less than a deep freezer.

    If what you want to power doesn’t exceed the wattage of the actual solar system, you don’t need to worry.

    If you’re exceeding the wattage of your system, this can lead to the components of the solar system becoming damaged.

    Did You Find Our Blog Helpful? Then Consider Checking:

    • How Much Does a 12kw Solar System Produce
    • How Much Power Does a 7kw Solar System Produce Per Day
    • How Much Energy Does a 6kw Solar System Produce
    • How Much Power Does a 3kw Solar System Produce
    • Solar Battery Storage System Cost
    • Add Battery to Solar System
    • Should I Get a Battery with My Solar System
    • Solar Heating System
    • Solar Systems for Cabins
    • Average Residential Solar System Size
    • Solar Power System
    • Solar PV System
    • Ground Mount Solar System
    • Off Grid Solar System
    • Off Grid Solar System Components

    SESS 5000 Watt Portable Solar Generator Kit

    Portable solar generator kits includes everything for a complete installation: solar panel, solar bracket, solar battery, solar inverter, solar charge controller, cables and other terminals. 5000 watt solar generator kit DC48V to AC110V/220V, 4DC12V, 4USB5V, and has 25440Wh energy storage every day.

    • Type : Solar Generator Kits
    • Place of Origin : Foshan, Guangdong, China
    • Brand : XINDUN POWER
    • MOQ : 1 pcs
    • OEM : Yes

    Solar Generator

    Solar Panel


    Choose XINDUN portable solar generator kits, you can get the following convenience:

    Complete solar solutions including all components. Professional configuration. Time-saving on the selection. Convenient after-sales maintenance: solar panels, batteries, solar inverter generator, all duties to one company.

    ■ Portable Solar Generator Kit Description

    Xindun portable solar generator kit is the most complete configuration on the market, which includes all necessary components: solar panel, solar bracket, solar battery, solar inverter, solar charge controller, pv cables, battery cables and other terminals. Significantly, solar battery, solar inverter and solar charge controller are all in one solar generator cabinet. After the simple installation is complete, it can be directly used for house appliances.

    Each set portable solar generator kit has power onoff test 100 times per hour. Each step of production is under strict quality control. Perfect protection: short circuit, over-voltage, low-voltage, overload, insulation resistance, high temperature protection.

    Xindun portable solar generator kit range is from 300W to 100KW. We provide customers with free solar solution design and can accept customization. This page introduces the 5000 watt solar generator kit, which can be used for dc and ac loads with total power not exeed 5kw.

    ■ Portable Solar Generator Kit Configuration

    SESS502W 5000W Solar Generator System Configuration
    Brand Xindun Model No. SESS502W Inverter Rated Power(W) 5000
    Maximum Load(W) 5000 Batter Capacity(AH) 800 Solar Panel Power(W) 2640
    Product No. SESS502W Certification CE Sunshine Duration 6
    Output Voltage (Optional) 220V Frequency (Optional) 50Hz/60Hz PV daily generating capacity ( Wh ) 15840
    Actual Load ( KW) 5 Actual Load day(s) 1 Actual Load time(hours) 3
    DC Output Port 12V 4pcs USB Port 5V 4pcs DC Lines 4pcs3W bulbs 4pcs5m wires with switch
    G.W. 794 Volume 1.78 20GP Loading Quantity Contact Xindun
    N.W. Contact Xindun DC Voltage(VDC) 48 Customized or not YES
    Configuration Details
    Product Name Specifications Quantity Remark
    Solar Panel Polycrystalline 330W 8 2pcs in series , 4groups in parallel
    Solar inverter 48VDC 5KW 1 ESS502W inverter built-in solar generator
    Solar Charge Controller 48VDC 60A 1 MPPT built-in solar generator
    Lead acid battery 12V200AH 4 Battery built-in solar geneartor
    Battery connecting cable standard 1 Built-in solar generator, connection between batteries
    DC Output Port 12V 4 4pcs 3W bulbs 4pcs 5m wires with switch
    solar panel mounting bracket Aluminum 1 Simple type
    PV combiner without 0
    Lightning protection distribution box without 0
    battery collecting box without 0
    M4 plug (male and female) standard 7 4 pairs 1 in 1 out, 3 pairs 2 in 1 out
    PV Cable 4mm² 100 Connection between solar panel and PV combiner
    Battery cable standard 1 Built-in solar generator, connection between batteries and solar hybrid inverter
    Package wooden case 1
    Electrical Load Reference List
    Electrical Appliance Rated Power(pcs) Quantity(pcs) Working Hours Total
    LED bulbs 20W 10 8Hours 1600Wh
    Mobile phone charger 10W 5 4Hours 200Wh
    Fan 60W 5 8Hours 2400Wh
    TV 50W 1 8Hours 400Wh
    Satellite dish receiver 50W 1 8Hours 400Wh
    Computer 200W 1 8Hours 1600Wh
    Water pump 600W 1 1Hours 600Wh
    Washing machine 300W 1 1Hours 300Wh
    AC 2P/1600W without
    Microwave oven 1000W 1 1Hours 1000Wh
    Printer 30W without
    Printer 30W without 1Hours 40Wh
    A4 copier (printing and copying combined) 1500W without
    Fax 150W without 1Hours 150Wh
    Refrigerator 200W 1 24Hours 1500Wh
    Water heater 2000W without
    Total 10190Wh

    ■ Portable Solar Generator Kit Wiring Diagram

    Contact XINDUN for more high-definition wiring diagram.

    ■ Portable Solar Generator Kit Parts List

    Solar panel: 1. Front Glass: 3.2mm, Anti Reflection Coaring, High Transmission, Low Iron, Tempered Glass. 2. Frame: Anodized Aluminium Alloy. 3. Warranty: 25-years performance warranty. 12-years warranty on materials and workmanship.
    Solar generator: 1. Combine inverter/solar controller/battery all in one cabinet. 2. Built-in 48V/60A MPPT solar controller. 3. Built-in 48V/5000W solar inverter.

    Built-in 4pcs 12V/200Ah battery.

    Low frequency pure sine wave output.

    Multiple output: 2AC output socket, 4DC 12V, 4USB.

    With 4pcs 3W bulbs, 4pcs 5m wires with switch.

    LVD/HVD/Charging voltage adjutable, suitable for kinds of battery.

    Automatic AC charger and AC mains switcher, switch time ≤ 4ms.

    AC charging current 0-30A selectable.

    Cables and parts:

    4mm2 PV cable 100m. PV cable is a special type of cable used in solar generator kits. It has the characteristics of high temperature resistance and friction resistance, and has a long service life.

    ■ Portable Solar Generator Kit in Real Production

    ■ Portable Solar Generator Kit Application

    Xindun portable solar generator kits have been sold to more than 100 countries, such as Nigeria, Ghana, Egypt, Botswana, Zimbabwe, South Africa, Egypt, Dubai, United Arab Emirates, Lebanon, Indonesia, Malaysia, Philippines, Columbia, Mexico etc. Solar generator kits have been widely used in: solar home, solar school project, solar hospital project, solar farm project, solar hotel project, solar millitary project, solar energy water treatment equipment project, solar goverment project, hilltop, ship, etc.

    ■ About Xindun Power

    generator, sizing, guide, off-grid

    ■ Solar Generator Kits Factory

    ■ Qualifications and Certificates

    ■ Global Solar Exhibitions

    ■ FAQ

    Q1: Are you a factory?

    A: Yes, we are the top 10 power supply manufacturers in China, with over 10k square meters production area. We FOCUS on solar system solution, inverters, solar charge controllers, solar generators and UPS power supply. We cooperate with some famous brands all over the world, can provide OEM/ODM production.

    Q2: Is the solar generator kits solution always the same? Can I customize one? A: We have professional teams making solar solutions for our clients. Solutions are mainly customized based on different sunshine time and power consumption. So each set solar generator kits may have different configuration. We\’d be happy to customize for you, contact XINDUN to know more details.

    Q3: What is the price of solar generator kits? A: Tell me your requirements, such as power generation demand, configuration, and whether there are other functional requirements. We will give you the most favorable ex factory price. solar generator kits factory direct sales, no middlemen earn price difference.

    Q4: What is the lifetime of the solar generator kits? A: Solar panel’s lifetime are 20 years, solar inverters 3~5 years, solar charge controllers 3~5 years, batteries 1~3 years.

    Q5: What services can XINDUN provide? A: We will provide solar generator kits free site survey, design, production, installation guide, maintenance of one-stop service, value added services: market and product training services, 24 hours after-service consultancy just for you and to make your problem to solveeasily.

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