Solar Inputs Explained
The solar section tells GridGap how much energy each panel can contribute, how much useful sun is available, how much real-world loss should be expected, and whether the array must also recharge the batteries after night-time use.
What the solar section controls
In a solar-hybrid scenario, the solar inputs do more than produce a headline panel count. They shape daily energy harvest, advisory controller limits, cloud-adjusted comparisons, and how much extra solar is needed if the array must restore battery energy as well as support daytime loads.
Some of these fields are straightforward even in early planning. Others are more technical and only appear in Technical mode. The key thing is to stay realistic. A solar result can become overly optimistic very quickly if sun hours, losses, or recharge expectations are too generous.
Panel and production fields
Panel profile lets you choose a stored panel default set that can populate panel wattage and typical Vmp and Voc values. This is a good starting point when you already have a likely panel family in mind.
Preferred panel size is the watt rating of one panel. This is the field that GridGap uses when turning required solar wattage into a practical panel count. Typical examples would be 450 W or 550 W panels.
Panel voltage (Vmp) is the panel voltage at maximum power. Panel voltage (Voc) is the open-circuit voltage. Both can be prefilled by the selected panel profile and adjusted in Technical mode if needed.
These voltage fields do not mainly change the energy side of the result. They matter because the controller and advisory string guidance must still fit a plausible real panel arrangement.
Average daily sunshine hours is one of the most sensitive solar fields in the app. It refers to average peak sun hours per day, not simply total daylight. A value such as 5.5 means about 5.5 effective full-sun hours. This distinction matters a lot. Long bright days do not automatically mean high peak-sun energy production.
Efficiency and cloudy-day fields
Installation efficiency profile tells GridGap how much real-world loss to expect from the solar installation. Choose the profile that best matches the expected installation quality and loss level.
If you choose the custom profile, the form shows Installation efficiency (%). This is the place to enter a custom real-world efficiency value rather than using one of the built-in profiles.
In Technical mode, MPPT efficiency (%) appears as well. This tells the app how efficient the controller or MPPT stage is. Even if the array itself is well sized, poor controller-stage efficiency can reduce how much of that energy actually reaches the battery and load.
Technical mode also adds Include cloudy-day scenario. This lets you test the installation against more difficult weather assumptions. If you turn it on, the form shows Cloud profile, where you can choose how severe the cloud reduction should be or switch to a custom value.
If you choose the custom cloud option, Cloud factor (%) appears. This is the remaining percentage of normal solar production under cloud cover. In other words, a lower value means a more severe drop in solar output.
Battery recharge fields
Include extra solar to recharge batteries is a major decision point in the solar model. If selected, GridGap calculates how much battery storage was used during the night-time scenario and adds that to the required daily solar energy.
This means the array is not only covering daytime loads. It is also being asked to replace some or all of the battery energy used earlier. That often increases the recommended array quite sharply.
If you enable that option, Night battery recharge target (%) appears. This is how much of the previous night's battery use you want solar to replace. A 100% target means solar is expected to fully restore that night usage. A lower target can make sense when another charging source will still help.
MPPT Limits
In Technical mode, the nested MPPT Limits section appears. Use Default MPPT Limits tells the app to use the stored profile for the selected inverter system voltage.
If you turn that default off, the form shows Max PV Voltage (V) and Max Charge Current (A). These are manual controller-limit overrides.
These fields matter because the solar result is not just about total energy demand. The final array also has to remain within a plausible controller envelope. This is why the solar result and solar controller result should be read together.
Installation and planning fields
If you enable Installation & Protection, the solar side picks up a wider planning layer. This includes practical PV-side details such as cable runs, cable material, cable type, voltage-drop allowance, installation environment, and protection choices.
These inputs support the advisory installation guidance later in the results. They do not replace final string design, final wiring design, or manufacturer checks. GridGap remains a preliminary sizing and planning tool.
A useful way to work is to settle the main production assumptions first, then return to the installation layer once the likely panel size, panel count, and controller direction are making sense.