You need to know this if you are planning a solar lighting project.
Warranties on the respective components are just that, and the terms and duration may differ on each of the components.
A performance guarantee that the predetermined lighting level (whether it be to Australian Standards or not) and the hours that the light is to be at level, and with how many hours (or nights battery back-up) that system will provide.
You really should make sure you get both strong warranties and a performance guarantee.
The relevance to this is that many solar lighting systems start to dim as soon as the battery starts to lose voltage, therefore in a fairly short period of time is not providing the pre-agreed light levels for the pre-agreed hours. This is not usually noticeable to the human eye until it is quite extremely dimmed.
So this how some solar lighting suppliers miraculously offer high lighting levels from a disproportionately small solar panel and/or battery. Remember it is a straight power in/power out equation, nobody has the silver bullet when it comes to batteries or solar panels.
If one supplier is offering a brighter light with the same size solar panel/battery, or the same wattage light for the same hours with a smaller solar panel/battery, you are not receiving more for less, you will end up with an unreliable solar light and a premature battery replacement (batteries are one of the most expensive parts of a solar lighting system, and the added cost for labour and travel time to site to replace makes this a very expensive exercise).
Pleases note, a performance guarantee does not mean the supplier will guarantee a solar light will not go out for the duration of the guarantee. If prolonged bad weather exceeds the battery back-up (autonomy), or the solar light is installed in a location with shade (or more shade than pre agreed with the supplier) the performance guarantee will not necessarily stand.