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Eco solar charge controller. What are RV solar panels?

Eco solar charge controller. What are RV solar panels?

    ECO-WORTHY 1500W Hybrid All-In-One Solar Charge Inverter 24V DC to 230V AC with Built-in 30A MPPT Charge Controller 1500W Pure Sine Wave Inverter for Home RV Camper Shed Solar Panel System​

    If it is any good (maybe) then I would like to try it. I will soon know if it is any good and because it is on Amazon, should have no problems returning it.

    Anyone on here tried one? Its just that I like the idea of not having a makeskyblue solar charge controller and a separate inverter if this eco jobby works. thanks in advance.

    OffGridInTheCity

    Don’t have hands-on, nor have I read about this brand but the price ~270 seems OK / lower end for sure. There’s always a risk of how well long it will work and likely no support. Also, do you plan to expand?

    For example, the MPP Solar LV2424 ( https://www.ebay.com/itm/274725361463 ) is in the same lane but beefier specs at 540. MPP Solar has a pretty good name for middle tier and if you plan to expand you can parallel 2 of these for 240v/120v. Not pushing MPP Solar, just using it as an example of a next tier up.

    On the other hand, there’s nothing wrong with starting modest as this will give you good hands-on experience (settings, monitoring, life-span, etc) and will help you with future equipment review.

    Integrating your solar panels

    Gain insight into your energy production by integrating your solar panels into Home Assistant.

    If you also set up the Solar Forecast integration, you will be able to see expected solar production and automate based on planned production.

    Hardware

    Home Assistant will need to know the amount of energy that is being produced. This can be done in various ways.

    CT clamp sensors measure the instantaneous current passing through an electrical wire. To translate this into electrical power (W) you also need a voltage measurement, because Power = Current x Voltage.

    In Home Assistant we have support for off-the-shelf CT clamp sensors and you can build your own with ESPHome’s CT Clamp Current sensor.

    The off-the-shelf solution that we advice is the Shelly EM. The device has a local API, updates are pushed to Home Assistant and it has a high quality integration.

    solar, charge, controller, panels

    Attention! Installing CT clamp sensor devices requires opening your electrical cabinet. This work should be done by someone familiar with electrical wiring. Your qualified installer will know how to do this.

    V LiFePO4 Battery Voltage Chart

    Here’s a printable version of the above chart:

    And here it is graphed out:

    24V lithium iron phosphate batteries are another popular option for DIY solar power projects. You can either buy a 24V LiFePO4 battery off the shelf, or get two identical 12V LiFePO4 batteries and connect them in series to make a 24V battery bank.

    They are fully charged at 29.2 volts and fully discharged at 20 volts. They are made by connecting eight 3.2V LiFePO4 cells in series.

    24V LiFePO4 Battery Charging Parameters

    • Charging voltage: 28.4-29.2V
    • Float voltage: 27.2V (or disabled)
    • Maximum voltage: 29.2V
    • Minimum voltage: 20V
    • Nominal voltage: 24V or 25.6V

    V LiFePO4 Battery Voltage Chart

    Here’s a printable version of the above chart:

    And here it is graphed out:

    48V batteries are more popular for larger solar systems. They rarely make sense for small-scale projects. Designing a higher voltage solar system allows you to keep amperage low, thereby saving you money on wiring and equipment costs.

    48V LiFePO4 batteries are fully charged at 58.4 volts and fully discharged at 40 volts. They are made by connecting 16 3.2V LiFePO4 cells in series.

    48V LiFePO4 Battery Charging Parameters

    • Charging voltage: 56.8-58.4V
    • Float voltage: 54.4V (or disabled)
    • Maximum voltage: 58.4V
    • Minimum voltage: 40V
    • Nominal voltage: 48V or 51.2V

    V LiFePO4 Cell Voltage Chart

    Here’s a printable version of the above chart:

    And here it is graphed out:

    Individual LiFePO4 cells have a nominal voltage of 3.2 volts. They are fully charged at 3.65 volts and fully discharged at 2.5 volts.

    You can buy individual LiFePO4 battery cells online. They’re best used for making your own lithium batteries. You can wire cells in series and parallel to make LFP batteries with your desired voltage and capacity combinations.

    3.2V LiFePO4 Cell Charging Parameters

    • Charging voltage: 3.55-3.65V
    • Float voltage: 3.4V (or disabled)
    • Maximum voltage: 3.65V
    • Minimum voltage: 2.5V
    • Nominal voltage: 3.2V

    Ways to Check LiFePO4 Battery Capacity

    Measure Battery Open Circuit Voltage with a Multimeter

    Pros: Moderately accurate

    Cons: Must disconnect all loads and chargers and let battery rest

    A battery’s voltage changes depending on its charge and discharge rate. Plus, LiFePO4 batteries have a relatively flat discharge curve from around 99% to 20% capacity. Because of these factors, it can be hard to estimate their state of charge from voltage alone.

    To get an even somewhat accurate estimate of LiFePO4 battery capacity based on voltage, you first need to disconnect any loads and chargers from the battery. (Don’t forget to disconnect your solar panels from your charge controller first!)

    Let the battery rest for a little while — I usually wait 15-30 minutes — and then measure its open circuit voltage with a multimeter.

    Compare your measurement to the right voltage curve above, or the state of charge chart in your battery manual. Use it to get a rough estimate of your battery’s remaining capacity.

    For example, I own the Ampere Time 12V 100Ah LiFePO4 Deep Cycle Battery (Ampere Time has since rebranded to “LiTime”). I wanted to check its capacity after having stored it for a few weeks. I brought it out of storage and measured its voltage with a multimeter. I got 13.23 volts.

    I then compared this number to the 12V LiFePO4 state of charge chart above, as well as the one in the battery manual.

    Based on the charts, I’d estimate my battery’s state of charge was somewhere around 80%.

    I like this method best for estimating the state of charge of an LFP battery I’ve just received or just pulled out of storage. The battery is already at rest and not connected to anything. I find it too inconvenient to disconnect everything once the battery is in use.

    DIY lithium battery builders will also measure the voltage of used (and new) battery cells — such as LFP cells and 18650 lithium batteries — to see which are good and which are duds.

    Use a Battery Monitor

    Pros: Most accurate, convenient

    Cons: Good battery monitors are expensive

    The best way to track battery capacity is to connect a good battery monitor — such as the Victron SmartShunt or Victron BMV-712. For my recommendations, check out my review of the best battery monitors.

    Battery monitors track the amount of amp hours consumed to accurately estimate the state of charge. They also display useful system specs such as battery voltage and current. Some connect via Bluetooth to your phone so you can check your LiFePO4 battery’s capacity in a mobile app.

    Use a Solar Charge Controller

    Pros: Convenient

    Cons: Inaccurate

    “My solar charge controller already measures battery voltage. I can just use it to check battery capacity.”

    solar, charge, controller, panels

    This voltage reading is largely inaccurate. It suffers from all of the problems mentioned above, plus it’s done while the battery is connected to loads and chargers.

    (Not to mention that some charge controllers have incorrect voltage readings.)

    For example, recall that when I checked my battery’s voltage with a multimeter at the battery terminals, I got a voltage reading of 13.23 volts. That correlates to a roughly 80% state of charge.

    But when I connected my battery to an MPPT charge controller, the controller measured 13.0 volts. That correlates to a roughly 30% state of charge — a difference of 50%! Granted, some charge controllers have much more accurate battery voltage readings than others.

    After all, voltage drops under load. And a charge controller is a load. If I were to connect a solar panel and start solar charging the battery, its voltage would quickly jump.

    Checking battery capacity this way is convenient. But beware that it can be quite inaccurate. I generally use this voltage reading just to make sure my battery isn’t close to being fully discharged.

    Installing an RV solar panel system

    Initially, Galiardi and Hutchison had a friend with experience in the solar industry help them build a small, rudimentary solar system. After a few years, they upgraded their system and even earned a sponsorship deal with a solar panel company.

    There are three main kinds of solar panels for RVs: monocrystalline, polycrystalline and amorphous.

    • Monocrystalline panels are the most efficient of the three, so they’ll generate the most energy in the least amount of time.
    • Polycrystalline panels are slightly less efficient, but they’re a durable and reliable option.
    • Amorphous panels aren’t as efficient as their counterparts, but the thin and bendable construction makes them easy to install and a lighter-weight option.

    In addition to solar panels, you’ll need several other components to complete your RV solar system, including the following:

    • Solar inverter, which converts the solar energy from DC to AC power.
    • Charge controller, which protects the storage system from overcharging.
    • Solar battery, which stores the generated energy.

    Because it can be difficult to keep batteries topped up solely by using solar, a backup source of power is also a good idea. Many travelers use some sort of gas or propane generator. Galiardi and Hutchison are equipped to charge up their lithium batteries using their truck while driving.

    Self heating batteries are fantastic if you’re camping in any sort of colder climates, Galiardi says.

    This is typically more of a need with lithium batteries, which can be more efficient, lower maintenance and longer-lasting than flooded lead-acid batteries, but are also more sensitive to cold.

    Finally, a cord to plug into the grid to recharge when it’s available is also a must for most.

    RV solar panel maintenance

    There’s little maintenance to worry about with solar panels. If you’re traveling in very dusty or windy conditions, you may need to wipe off or clean your panels to ensure they’re working at maximum efficiency.

    Traveling may also add a bit more wear to a panel’s connectors. Standard solar panel connections are quite weatherproof, but it’s worth inspecting your system periodically for signs of deterioration, loose connections or rust.

    solar, charge, controller, panels

    It’s not recommended to service these parts on your own without the guidance of an experienced electrician. Remember that a panel can be generating energy any time the sun is up, even when it’s cloudy, so always treat any connections as live circuits.

    Cost and rebates

    The overall cost of your system will depend on factors including the type of panels you choose and how much electricity you need to generate. If you need lots of power, you’ll need to buy more equipment, driving up the price.

    Galiardi and Hutchison said their 300-watt system with batteries, inverter and other components cost about 3,000, while larger systems for bigger RVs can easily run more than twice as much.

    The good news, according to Galiardi, is that incentives, including the 30% federal tax credit for home solar systems, can apply.

    It includes second homes. And RVs and boats and off-grid cabins are in that second home realm, Galiardi said.

    Are RV solar panels right for you?

    It’s difficult to argue with the benefits of solar energy, but RV solar panels might not be right for everyone. If you live in your RV and often take it off-grid (where there are no campground hookups), then solar can be a convenient and eco-friendly alternative to gas-powered generators.

    Portable and flexible solar panels better suited to RVs may be more expensive than standard rooftop residential panels, but they’re still remarkably cheap compared with past eras.

    There’s little reason not to boost your freedom by adding a solar system to your rig if you can afford it, though if you use your RV infrequently, it may not be worth the investment.

    Hutchison noted that there might be no need for panels if you only ever park your RV at developed campgrounds with provided power.

    However, he added it’s worthwhile to consider a system with panels and batteries, even if you plan to spend even one night off-grid between those sites.

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