General solar FAQ
Solar panel and a method for mounting/securing, gland cable entry to campervan or boat, solar charge controller, lithium batteries, battery monitoring, switches, fuses/circuit breakers, busbars, cables, connectors, heat shrink, tools for making connections.
- Method 1: Call us and we can help you with the calculations 01803 446 109
- Method 2: Learn how to do it yourself using our video tutorial “How to size a boat solar system”.
Its normally best to fit as many panels onto a van or boat due to the limited space. For other applictions, the number of solar panels depends on your batteries, charge controller, demand for energy and of course budget.
If adding extra solar panels, it is often preferable to add a seperate charge controller.
See our video tutorial “How to size a boat solar system”.
The battery capacity is determined by your demand for energy and the size of your solar system.
See our video tutorial “How to size a boat solar system”.
A fuse is needed to protect the DC wires. The size of fuse depends on the size of the cable, its length and other factors such as temperature. The fuse should be positioned as close as possible to the battery. Additionally, always follow the manufacturers instructions.
See our video “Wiring lithium batteries for a boat 5 tips“
Off-grid 12V solar systems provide energy independence, reduced reliance on fossil fuels, and lower long-term energy costs. They are ideal for remote locations, camping, boating, and emergency backup power.
The size of your off-grid solar system depends on your energy consumption, available sunlight, and the capacity of your batteries. Consult with our experts to determine the optimal size for your needs.
Lithium-ion (LiFePO4) batteries are generally the best choice for off-grid 12V solar systems due to their high energy density, long lifespan, and low maintenance requirements. They are typically less expensive than lead acid batteries when compared like-for-like.
Regular maintenance includes cleaning the solar panels, checking the battery health, inspecting wiring and connections, and ensuring that the charge controller and inverter are functioning properly. Follow the manufacturer’s guidelines for specific maintenance tasks.
The lifespan of an off-grid solar system depends on the quality of the components and maintenance. Rigid glass solar panels typically last 25-30 years, flexible solar panels around 10 years, while lithium batteries can last 5-10 years or more, depending on the usage.
You can monitor the performance of your off-grid solar system using a battery monitor. See out tutorial “Monitoring Options” which gives specific recommendations.
Solar panels FAQ
Use a soft-bristled brush or a non-abrasive sponge and unpressured water. Typically harsh chemicals including detergents should be avoided. Always turn the solar system off and avoid cleaning when the solar panels are hot. Always check the manufacturer’s guidelines.
The datasheet output is measured at standard test conditions which is irradiance 1000W/m², cell temperature 25°C, air mass 1.5. Real life output is impacted mainly by shade, sunlight (irradiance) and angle of the solar panels to the sun (incidence). But other factors also have an impact such as solar cell temperature; age of the panels (degredation) and dirt on the panels.
Connecting solar panels in series increases the overall voltage of the system. Connecting solar panels in parallel increases the overall current of the system. You typically match the solar panels to the charge controller and this determines whether to wire in series or parallel. See our tutorial on MPPT charge controller sizing.
No you should not walk on flexible solar panels as they are not designed to withstand the concentrated pressure of footsteps. Walking on them can cause micro-cracking of the silicoln cells and is likely to impact long term performance.
Flexible solar panels are designed to be bendable and conform to curved surfaces. However, they typically have a maximum bend radius and sharp bends should be avoided. Repeated bending and unbending can damage the solar panels. Always follow the manufacturer’s instructions.
Historically there we differences in efficiency and cost between monocrystalline and polycrystalline solar panels, but now there is little difference between these technologies.
While solar panels are most efficient in direct sunlight, they can still produce energy in cloudy conditions. The amount of energy generated will be significantly lower.
While it is technically possible to mix different brands, models and ages of solar panels, it is generally not recommended due to potential issues with performance, compatibility, warranty and maintenance. It is often better to add another charge controller. If in doubt call us for advice.
The power of a solar panel is measured in watts. So a solar panel rated at 300W will produce more energy than a 100W solar panel in the same conditions. The power of a solar panel does not indicate it’s efficiency.
Cell efficiency measures the efficiency of a single solar panel cell. Cell efficiency is largely irrelivent in a purchasing decision and is often used as a marketing tool. What is important is the module efficiency which indicates how efficient the solar panel is.
Less efficient solar panels are typically lower priced per watt. But other factors to consider are the cost of mounting, labour and wiring; and the available space. For small spaces such as boats and campervans it is generally better to buy high efficiency solar panels.
Flexible panels are ideal for curved surfaces and portable applications, while rigid panels are best suited for flat surfaces and fixed installations. See our tutorial “Rigid or flexible solar panels?“
Charge controller FAQ
PWM (Pulse Width Modulation) charge controllers are typically less expensive. MPPT (Maximum Power Point Tracking) charge controllers are can extract more power from the solar panels. We recommend MPPT type solar charge controller when there is are shade conditions such as on a boat, campervan or caravan or when there are cloudy conditions. See our tutorial “MPPT or PWM charge controllers?“
In most cases yes, but there are exceptions. See our tutorial “Do I need a solar charge controller?”
It’s a fairly complex process so see our tutorials “Sizing MPPT charge controllers” and “Sizing PWM charge controllers” and call us for expert advice.
Solar charge controllers, which are also called solar regulators, are effectively an intelligent battery charger.
See our tutorial “What is a solar charge controller?“
Most modern solar charge controllers now feature Bluetooth, which makes it convenient to see on your phone how your solar system is performing.