I do not know about Electron. There is no charge for debit cards evidently. Plus of course the admin fee so the more you order the cheaper they are. I just used a CC Visa card as at least there was some fall back, if anything went wrong. I have a Gold Card from Camping Cheques which is cheaper for admin fees, but of course you have to pay for the card to begin with. I guess you can add about 50p per cheque to cover the extra costs.
I also have a Bread card which is a Pay as you Go type Mastercard. I top it up at the PO and use it for internet shopping as they can only steal the balance, which is never that much. I do not trust Paypal as I have had a bad experience.
I also heard Ryanair were going to start charging for Electron as well, as they want all your cash which ever way they can. I do object to the so called budget airlines charging for a seat. Fair enough if you wish a special one, but just any old seat?? What do they expect, we are to hang from a roof strap for the flight?? I tend to use regular airlines, yes maybe a bit more expensive, but suprisingly not that much, but the seat is included as is your baggage and they serve tea and coffee as well. Plus if you miss a connection they pay the hotel.
I regret (no I don't) I avoid Ryanair like the plague. Starve them of cash and they may decide customers are important after all.