Suggested system for new campsite sanitation block

[forestview]

Good afternoon
We have just purchased a campsite in Normandy, France. It is in need of a new sanitation block as the current one is in decay. We are now considering all the different methods of supplying hot water for the showers and basins plus heating in winter.
In france most hot water is produced by mains fed immersion heaters but we are keen to look at alternatives including combi boilers, electric, air source heat pumps etc
We are told we have between 3 to 5 bar mains pressure
We need to supply 6 showers, 6 basins and heat a 72sqm well insulated building.
Q1. how much mains pressure will it take to deliver 6 decent showers at the same time?
Q2. How do we stop pressure and temperature fluctuations as showers/basins get turned on and off
Q3. How much water does the average shower consume whilst providing a decent quantity of water.
Q4. Does anyone know of a good consulting plumbing engineer who could advise and or implement the system here in Normandy (free accommodation!! )
Q5. We are told air source heat pumps could save us a fortune and provide all the hot water and hating we would need for a building of this size. Anyone got any advice or experience of these or indeed a good source of un biased information as manufacturers tend to believe extrordinary things of thier products
Sorry for the barrage of questions but we seem to go round and round in circles and we were hoping for some clarification as to the best allround way to tackle this.
Thanks to anyone taking an interest in our little challenge.
Peter

 

[TicklyT]

Not many answers, but, as far as Q1& 2 go, the flow rate from your mains water supply is more important than the pressure. You could have, say, 10 Bar pressure available, but it will be of little use if the pressure drops to zero when delivering 5 litres per minute.

Conversely, your supply may be capable of delivering more than, say, 50 litres per minute with a minimal pressure drop.

 

[forestview]

Hi TicklyT
thanks for that - was not aware. Dumb question... how does one go about checking volume not just pressure?
cheers again for taking the time to reply to my post
Peter.

 

[dcawkwell]

You need unvented cylinders (2) heated by whatever takes your fancy.
Air source heat pump, lpg boiler, gas boiler, oil boiler
Plus accumulator tanks to store a quantity of cold water at pressure.

Sorted.