Many people wonder if they can charge both their ebike and a 12V battery at the same time using solar power and a Car Power Inverter. The short answer is yes, it is possible to charge both simultaneously from solar power. However, there are important factors to consider to ensure efficient and effective charging.
Understanding Solar Charging Dynamics
Harnessing solar energy involves converting sunlight into usable electricity. Solar panels are quite efficient, typically around 80-90%. On a sunny summer day, you can expect about 5 hours of “full sun” equivalent. A 100W solar panel, under these ideal conditions, can generate approximately 400-450 watt-hours (Wh) of energy per day. This generated solar power can then be used to charge batteries through a car power inverter. The inverter plays a crucial role by converting the 12V DC power from your battery (which is charged by solar) into 120V AC power, which is what most ebike chargers and other standard appliances require.
Simultaneous Charging: Feasibility and Considerations
When you connect both an ebike charger and a 12V battery charging system to a car power inverter powered by solar, the system will attempt to charge both. However, the ebike battery might charge more readily. This is because if there’s sufficient charge in the 12V battery to run the inverter, the solar panel will be charging the 12V battery and powering the inverter simultaneously. If the solar input is insufficient or the 12V battery charge is low, the voltage under load might drop below 11V, causing the inverter to shut down.
For this setup to work effectively, especially for charging both an ebike and maintaining a 12V battery, several factors are critical. Firstly, ensure your 12V battery bank is adequately sized. A minimum of a 90-100Ah 12V battery is recommended, and ideally, it should be fully charged at the start. A standard ebike charger typically consumes between 100-140W. If your ebike charger is within this range and not excessively high (like 300W), a 100W solar panel setup can be feasible. However, a 150W ebike charger could potentially drain the 12V battery faster than a 100W solar panel can replenish it, leading to a deficit taken from the 12V battery. Upgrading to a 200W solar panel setup can provide a more comfortable power margin, but it also increases the size and portability considerations of your solar array. Keep in mind that charging a lead-acid 12V battery from 50% to full (99%) can take a whole day, as the charging process slows down significantly after reaching 80-85% charge.
Choosing the Right Equipment
For a convenient and portable solar charging solution, consider a “solar suitcase” like the Renogy 100W Solar Suitcase. These kits are designed for ease of use, folding compactly for transport and including a built-in solar charge controller. Simply connect it to your 12V battery with alligator clips, and you’re set. While these suitcase kits can be pricier per watt compared to permanently installed panels, they offer unmatched convenience for portable setups.
When selecting a car power inverter, a pure sine wave inverter is recommended, especially for sensitive electronics like ebike chargers. The Samlex Solar PST-300-12 is a reliable and reasonably priced 300W pure sine inverter that is well-suited for this application. While cheaper inverters may exist, investing in a quality inverter ensures stable and efficient power conversion for your devices.
In conclusion, charging an ebike and a 12V battery simultaneously using a car power inverter and solar power is achievable. Success depends on carefully considering the wattage of your solar panels, the capacity of your 12V battery, and the power consumption of your ebike charger. By selecting the right equipment and understanding the dynamics of solar charging, you can effectively utilize solar energy for your portable power needs.
