Storing fuel... is it just the ethanol to worry about?

[d000hg]

I want to keep a store of petrol for my tractor mower and other tools - and just for emergencies in case things get totally crazy.
I've used Aspen and Stihl products before but apart from being very pricey, I don't have a stockist nearby.
I've seen Esso sell a non-ethanol fuel but is it only the ethanol I need to worry about? We're talking a few months' storage not years, of maybe 20-30L.

 

[JohnD]

fuel storage preservative additives are popular among boatowners and you can get them from a yottie or canalboat chandler. It will absorb water and, if it is in the carb or fuel injectors, it may dry out and leave a sediment that blocks them (IME usually the pilot jets, which are small)

"Shell" used to do additives but I don't see them listed now.

examples
https://www.force4.co.uk/department/engines-inboard-outboard/fuel-treatments

 

[d000hg]

Do you know if "alkylate fuels" like Aspen include these already then? If I can get non-ethanol fuel from Esso I can probably buy additive online as a lower priority.
Thanks.

 

[Tigercubrider]

https://www.hse.gov.uk/fireandexplosion/petrol-storage-club-association.htm

Shell V Power has less ethanol than most. With my bikes I rotate fuel from the bikes to the car and top the bikes up with fresh fuel. American owners seem to use stabilisers.
With ethanol, the water settles out so a good shake of cans might help

 

[d000hg]

I don't know why is different in a few areas but:

Esso super unleaded petrol (Synergy Supreme+ Unleaded 97) is ethanol free (except in Devon, Cornwall, the Teesside area and Scotland).

 

[Burnerman]

If you are keeping fuel just from one season until the next, there's no need to do anything......just rotate the cans of course.
John