The power station and solar panel are complete, basically a solar generator. How it all works, when it’s worth buying, and what you should consider before you buy.
It is now important for some consumers to become independent of the public power grid. Because of rising energy prices, it certainly makes sense. Just what are the options? And are they also profitable? The acquisition costs of larger devices often only pay off after a longer period of use and are only sometimes sensible. We have tips for purchasing solar generators – for larger models at home and smaller ones on the go.
What is a solar generator?
In general, generators convert mechanical energy into electrical energy, electricity. There are different ways of generating electricity. A solar generator is done using solar energy. The device captures this with the support of solar cells, whose energy it then converts. Solar cells can be interconnected in groups of different sizes to generate even more energy. They must be integrated into a photovoltaic system to release the energy generated. With many interconnected small solar panels, the generator should have enough watts to be able to pass on the energy to electrical appliances in the household or on the road or to be able to store it.
For camping or on the go, smaller devices with a low wattage are sufficient to charge a cell phone or tablet. The advantage of a generator is that it can store electricity and does not have to pass it on directly. It can therefore serve as an emergency unit. A few solar panels are sufficient for this low-power generation or storage, which can also be practically folded up. As a rule of thumb, one square meter of a modern solar module can supply between 150 and 230-kilowatt hours of electricity per year. This can vary depending on the manufacturer, size, and model. Anyone considering a solar generator for the home to power smaller electronic devices will require a larger generator with higher wattage and correspondingly more solar panels.
What is there to consider when buying?
So before you buy a solar generator, you should know what it will be used for: for smaller devices on the go or larger electrical devices at home. Mobile solar generators or power stations generate less electricity, can be easily transported, and have slots and connections for devices such as smartphones or notebooks.
Household appliances typically require a higher voltage than small appliances and a solar generator capable of producing high wattage. These devices work with several collectors, i.e., several solar modules, which can be installed on the balcony, for example, or on the roof for even more power. Live in an apartment with a balcony and want to buy a larger generator with several solar panels. You can find more information in our article on balcony power plants.
A generator is not necessary for this. Still, it can be practical as an emergency generator, especially in the event of a power failure, because it can store enough electricity that can then be used to bridge the gap. In addition, a generator easily converts the stored energy into electricity, already has the appropriate connections for cables, and can even be taken into the mobile home when the next vacation is coming up, and electricity is needed.
How many watts is a solar generator?
With a large, powerful solar generator, up to 2400 watts can be generated. In this way, several household appliances can also be supplied with electricity. However, before you decide on a powerful generator and set up a corresponding number of solar panels if you are not the owner of your apartment or own your own home, you should clarify with the apartment owner whether you are allowed to set up the equipment.
If installed on the balcony, outputs of up to 300 watts are usually possible. If solar generators are installed on the roof, a maximum number of 2400 watts is possible. It would help if you chose the roof side south of the sun exposure to generate the maximum amount of electricity. When the sun doesn’t shine, or the solar panels are even covered with snow, you have to resort to other power sources.
Store the power station correctly
The most common avoidable damage or total failure of solar generators is caused by deep discharge and incorrect storage of the power station. Especially in the current times of potential power outages, it makes sense always to have a full power station available, but it also makes sense from a technical point of view. The following tips apply to power stations, any LiFePO4 batteries, and Li-ion-based batteries in bicycles, mobile phones, laptops, and bicycle lamps. (Generally, they apply to all battery types, lead and gel are dumb and don’t have a computer to protect them)
Suppose a discharged power station is parked longer, e.g., after the camping season. In that case, it may be scrapped, and a layperson may not reactivate it, but a professional may only be able to reactivate it for a short time. Power stations consist of a LiFePo4 or Li-Ione battery pack. Its small computer, the so-called BMS (Battery Management System), monitors this battery pack. This computer is only there to protect the physical battery (from its power or external charging power) and cannot be overloaded. The BMS controls active and passive protection functions.
Active protective functions that regulate permanently are the limitation of the charging power, the limitation of the discharge power, the depth of discharge, or the balancing of the individual battery cells. (if the danger for the battery is over, the battery works as usual)
Passive protection functions completely switch off the battery in the event of supposed damage, so it cannot be reactivated without disassembly. The battery is then defective and can no longer be used without checking and reactivation by a specialist. Defective but technically reactivated batteries pose a risk of fire and explosion. Such a deactivation occurs, for example, if there is suspected cell damage (some cells differ greatly from the charge of the other cells) – or the entire battery is deeply discharged.
Deep discharge must be avoided at all costs
A deep discharge cannot occur with regular use since the BMS switches off the battery before a possible deep discharge and only allows it to be discharged again after it has been charged.
The problem of deep discharge arises with very long storage or storage in the discharged state. A power station or a 12V lithium battery always consumes electricity. The voltage drops when not in use, but the BMS that monitors the battery always consumes some current, so the battery is always discharged even when not in use.
If an almost empty power station is now stored, the voltage drops further, and the BMS switches on the battery protection so the power station can no longer be discharged. In most cases, the power station can only be switched on again once it has been charged.
If the power station is still not charged, the battery voltage drops, and the cell protection becomes active. The BMS now suspects damaged cells and blocks recharging of the entire battery – to avoid the risk of fire and explosion. The battery can no longer be used, and cell damage may have occurred due to the deep discharge. (Battery material decomposes, short circuits, and leakage currents occur). If the battery were to be supplied with energy again through charging, small leakage currents would become large, and high temperatures could arise, leading to a fire.
The following tips for storing the power station correctly and ensuring a long service life
- Always recharge the power station as early as possible after use (not quickly, but as slowly as possible).
- If possible, never fully discharge the power station (especially not with large consumers)
- Never store the power station empty, but fully charge it before storing it for a longer period (winter) and then discharge it to approx. 85-95%, then switch it off
- Please switch off the power station completely before storing it (deactivate Bluetooth and W-Lan)
- Check the charge level of the power station every 1-3 months (if it reaches 50%, recharge)
- Store the power station in a dry, dust-free place between 10-20 degrees, avoid temperature fluctuations
- Fully charge the power station after storing it before using it for the first time (even if it says it is full)
A mobile solar generator can be worthwhile when camping and can be practical for a sustainable power supply. A balcony power plant or a large solar generator for the home with many solar panels on the roof can also pay off – possibly only in the longer term. However, a powerful generator at home is practical because it converts the energy from solar modules directly and can also be used in the event of a power failure or the mobile home, ideally with additional foldable solar panels to take with you.
A solar generator can also be useful in allotment or allotment gardens to obtain and store electricity and to serve as an emergency generator. There are also often enough opportunities to set up the panels. If you want to switch to solar energy permanently, you don’t necessarily need a generator. It is also important to be able to use other power sources when the sun is not shining.