Hot water tank insulation

Having used energy to heat up water, I find it goes cold quickly. Does anyone know if there is any way of insulating the tank / system?

I don't know what make/model of water heater is fitted to a 2011 Nuevo, but whatever it is, it will almost certainly already be insulated.

You may be able to add more around it, but the problem is one of thermodynamics more than anything else - the tank is relatively small (for obvious practical reasons) so its surface area is large relative to its volume, so it loses heat relatively quickly.

Adding insulation will help a bit, but be aware that water leaks around a water heater are not uncommon, so if you do it would be wise to use something (e.g. expanded polystyrene or a close-cell foam) that does not soak up water or otherwise hide a water leak.

Ours is the ??? Truma thingamajig hot water and heater all in one and when I looked at a cutaway at the NEC (to try and suss the burning plastic smell that we still get) there is virtually no insulation around the outer jacket. So, I have put some heat resistant silvered foam on and it has helped a bit. I have been careful not to cover the control part with the computer bits and bobs in though so as to avoid it getting too hot.

I've added loft insulation off cuts around and on top of our hot water tank, it works well in our Sigma,did the same in our last van,a 09 Nuevo.havent had any water leaks from tanks ,yet.  
Boaby

Thanks folks, mine is a Truma Ultrastore 10 litre and buoyed by your comments I had a look at my boiler. No insulation at all, just a fibreboard jacket. I have just found this thread and am going to add some appropriate insulation. https://www.autosleeper-ownersforum.com/t14103-truma-ultrastore-water-heater-insulation.
Cheers
Alan