Under the basic PFPTP ProFirst, any Independent candidate elected as MP would carry a voting power in the House exactly equal to the number of votes cast in the relevant constituency for that MP.
There is, however, the option that the votes for all successful Independent candidates could be scaled up so that the total voting power of all Independent MPs (i.e. those not affiliated to any political party) in each country in the UK would equal the total votes cast across the country for Independent candidates, whether they were elected or not, thus effectively treating "Independents" as a political party. This would mean that:
Alternatively, it could be decided that all votes cast for both Independent candidates and for those standing for small parties who do not poll enough votes to qualify under the supernumerary MP option if that were adopted, should be allocated to all elected Independent MPs in the proportion of their own votes. Otherwise, votes cast for such small parties with no supernumerary or elected candidate are simply lost to the system, as at present.
In the absence of the supernumerary MP option, then it is suggested that under PFPTP ProFirst all "wasted" votes should be allocated to Independent MPs pro-rata, as described above. It could of course be argued that that is giving Independent MPs an unrealistically large vote which does not necessarily reflect their electoral support. But in effect, that is what happens under the present system, only to a very much larger extent. A sitting MP currently carries a disproportionate and unrepresentative share of the voting power in the House compared with the number of voters out of the total electorate who voted for that candidate.
Ironically, of course, only one Independent MP was elected in the whole of the UK in 2010. That was in Northern Ireland, where only six Independents were standing. And of those, only two received a significant vote. The tables comparing the three electoral systems under discussion have therefore only allocated to the one Independent elected the actual votes received in that constituency. But it has to be acknowledged that in this instance, the AV simulation actually transferred sufficient second-choice votes to elect the only other Northern Irish Independent who had achieved a significant poll, having only just lost in the first round.
It should be noted that the proxy vote option, if adopted, would also have an effect on the final voting power of Independent MPs.