Earthing requirements...

Where there is no earth spike already installed ... a suitable one must be installed and bonded to the consumer earth terminal with a wire at least half the thickness of the phase conductor ... but not less than 6 mm.

But this note is rather interesting ... deosnt his mean that if you install a spike you dont need an SPD ... or if you install an SPD you dont need the spike.

NOTE 2 Protection of photovoltaics can be by means of or surge protective device
(SPD).

This section is one that seems to be a little confusing for many.

7.12.3.1.2 In an installation that is supplied from a combination of
transformers and alternative supplies located near to each other, the neutral
points of each of these items shall be connected to a single earthed neutral
bar (see P.1). This earthed neutral bar shall be the only point at which the
neutral of the installation is earthed. Any earth leakage device shall be
positioned in such a way as to avoid incorrect operation due to the existence
of any parallel neutral/earth path.
7.12.3.1.3 Where alternative supplies are installed remotely from the
installation, or from one another, and where it is not possible to make use of
a single neutral bar or neutral conductor which is earthed, the neutral of each
unit shall be earthed at the unit and these points shall be bonded to the
consumer's earth terminal (see 6.12.4). The supply from each unit which
supplies the installation or part of the installation, shall be switched by means
of a switch that breaks all live conductors operating substantially together (see
figures P.2 and P.4), to disconnect the earthed neutral point from the
installation neutral when the alternative supply is not connected (see also
6.1.6).
NOTE Where four pole switching is implemented, consideration should be given to use
overlapping neutral switching devices.
7.12.3.1.4 Where only part of an installation is switched to the alternative
supply in the same distribution board, the neutral bar shall be split (see
figures P.2 and P.3).