Is this better than jump leads ?

The EU standard voltage of 230 volts is a guide for member states .The EU directive allows for a - 10 % +6% varience so the voltage can be between 207 and 243.8 volts , any electrical equipment must function at these voltages .

At no time did the directive insist that member states modified thier power grids to comply , infact the tolerences were set so that all states could comply

Its perfectly correct to label each countries voltage at whatever that specific countries voltage is in our case 240 volt in poland 220 volts germany 230 volts

Its far easier though to give the mean as 230 volts when discussing europe

Europe though is not a country and to state no where in the EU uses 220 volts is incorrect

It's not incorrect to describe it as such, tis incorrect to specify it as such. When buying expensive bulbs you really want the 240V ones.

Conor submitted this idea :

The alternators native output is 3phase at in excess of 100volts AC. That is then rectified and regulated, with the help of the battery, to around 14v. Without the battery, regulation can be quite poor, certainly poor enough to take out Radios and any sensitive electronics. Large inductive loads such as the cooling fans and heaters switching, would make the spike situation worse.