They’re creating a lot of problems with their restrictions, aren’t they? You don’t mention any reason for the ban on these types of stoves (although, in the case of the petrol strove, it’s understandable, with lots of people camping), but it’s a shame, since gas stoves can be excellent at festivals. The problem is that what they’ve done severely limits the possibilities open to people, especially if you want to cook for a large number of people at once. In fact, pretty much just two are left – and the people behind the festival might frown on one of them.
You could use a barbeque that uses charcoal, not gas. It’s about as close as you’re going to get in size to the party stove you’ve had in the past. The problem is that you’ll need to take a fair amount of charcoal and you’ll need starter fluid – an item that might possibly be banned, if there’s a ban of petrol stoves.
However, it’s certainly worth asking, since it would be the ideal substitute, especially if you all want to cook together. On the downside, you’ll need somewhere to dispose of the ashes and cold charcoal, which isn’t always easy on a festival site.
The only other real candidate is to use solid fuel. It would fit the festival’s requirements, but it’s not so good for you. Granted, the stoves and the fuel itself is cheap, which is a big plus, but the real problem is that the stoves are small – you can fit one pot or kettle on them.
That means, of course, that you won’t all be able to cook together. Unfortunately, the options are limited, so these two are your prime choices (and disposing of the solid fuel blocks after cooking can be a bit messy, so be warned). Effectively, it means you might well have to change the way you cook at the festival, which will lessen your enjoyment of the event, but there might be no choice but compromise.
In other words, there’s no simple answer (unless it’s fine to barbeque, and even then you have the expense of a new grill), but hopefully the pleasure of the festival and friends will take the sting out of any revised cooking arrangements.