Re: "Higher prices mean cheaper electricity for everyone"
Money is Debt. Simple as that. Before money, people traded. If you didn't have anything that the guy you were trading with wanted then there was no trade. Debt\money allows a trade to occur with a deference of payment until a later date. As more people get involved in this it makes sense to trade debts
For example, Alice owes Bob 3 sheep and Bob owes Chaz 3 sheep. Bob can either transfer the debt or try and defer payment to Chaz in the hope that Alice pays up and he can shear the sheep before passing them on to Chaz, thus having something else to trade with and so it goes on...
Money is debt, investment of debt can lead to the creation of the ability to create more debt \money.
Of course if the sheep had died whilst I'm Bobs possession then Chaz might get a bit annoyed but that's the risk you take with investments.