You haven't mentioned in your query whether your installation is tri-phase or mono-phase. If it is an older system, then it is probably tri-phase, and if you have all the load on just one or two phases, then it will tend to trip out sooner as regards the total load being applied. If it is a tri-phase system, then you need to ensure that the load on the 3 different phases is as balanced as possible.
Whilst the solution proposed by Christian will probably work, you should have the system checked for phase balance first in the interests of safety, as routing the total load through just one phase can be dangerous due to overheating of the wiring.
Unlike in the UK, the EDF are only responsible for the safety of the system as far as the Meter, so just because they increase the overall total supply, it does NOT mean that it is safe to do this on your particular installation.
Probably best to have a qualified electrician look at the system. Due to the way that us Brits tend to use our electricity, it is often best to have an old tri-phase system converted to mono-phase. This may require some rewiring, or can be achieved by reconnecting the existing wires in a different way, or a combination of both.
Additionally, you should also have the earth connection checked, especially before increasing the total maximum available power. Particular attention must be paid to the gauge (thickness) of the earth cabling, as it MUST be capable of carrying all of the total current available in the event of a major short circuit.
Also a very good thing to check that the correct differential circuit breakers are fitted to protect the entire system. These are also known as Residual Current Devices (RCD) and Residual Current Circuit Breakers (RCCB). These devices monitor the balance of the current between the phase (live) and return (neutral) wires of the circuitry, and automatically cut the current in the event of the slightest leak. This prevents the possibility of electrocution or electrical fires. There are two slightly different types ---- one for water connected appliances such as the water heater, dishwasher, washing machine circuits, and the other type for the remainder of the circuits. Following this link will give you pictures of many different makes of differential circuit breakers which will give you an idea of what you are looking for on the main switchboard -- https://www.google.com/search?q=differential+circuit+breaker&hl=en-GB&rlz=1T4PRFF_en-GBFR553FR553&tbm=isch&imgil=nlpmQ9cmLIoCtM%253A%253BIA3MdIVe_3uXXM%253Bhttp%25253A%25252F%25252Fwww.theinternetelectricalstore.com%25252Fkanlux-kr6-250032-black-switched-grey-cased-differential-current-circuit-breaker-25-amp-4242-p.asp&source=iu&pf=m&fir=nlpmQ9cmLIoCtM%253A%252CIA3MdIVe_3uXXM%252C_&usg=__kxsYUReu3tLu0378vca6dWOTsT8%3D&biw=1093&bih=513&ved=0ahUKEwjWjpPk3v3LAhXI3iwKHXZ0CY0QyjcIQg&ei=TfUGV5a0Gsi9swH26KXoCA#imgrc=nlpmQ9cmLIoCtM%3A
What they all have in common is a 'test' button. If your installation is not equipped with these, then I strongly urge you to have them fitted as soon as possible.
Hope this helps. Robert.