Most people will not have the experience (nor the certification) to wire something like this directly into their home. I agree that the price is too high at the moment to make it economical - but if you assume a few hundred pounds for the equipment, the same again for an electrician to fit and certify everything, plus the cost of updating the software and maintaining an online portal, and a little profit for those behind it - the price is easy to understand. Ultimately, I think devices like this - solar power, storage, monitoring - will be built into new houses where the upfront cost can easily be absorbed.