Very interesting article. There is also a 3rd option it's called PowerVault but it uses lead acid batteries so has a limited life time and limited discharge capacity. What sort of batteries are in the Maslow ? I think these types of devices will be great in the future when the price comes down, but right now splashing out £2k or more for one of these seems like a real waste of money to me... I have a 9kWh leisure battery bank and inverter that I charge up during the day from solar power and at night I use it to power my computer equipment as I have a server running 24/7 as well as several switches, modems etc so my computing for the moment has no daily running costs saving me about £100 a year which in 2 years will have paid for itself in terms of cost of batteries. What I really don't understand is the pricing for these things... where do they get £2k from ? Assuming the customer has no understanding of wiring two / three leisure batteries together to a charger and inverter? I paid about £300 for my bats + inverter and I already have the capacity to charge batteries using my solar inverter.