Hi all,
Just a heads up.
Received the letter in the attachment yesterday, and since we have been looking at battery storage I figured I might as well spend a bit of time talking with them.
After a bit of forwards and backwards, during which the "offer" was designed to make me anxious to pay money and get involved, the "Closed group-Testing Phase" boiled down to the following:
1. Battery is a Lithium based unit having 3 kWhr of capacity.
2. The cost of the battery is stated at slightly north of $4000.
3. Sign up also commits you to a 5 year maintenance contract at slightly south of $2000 - ie $400 per annum
4. The deal also requires that you agree to allowing them to have access to the battery electronic internals via your LAN and then through the modem so battery data/performance can be uploaded for "analysis".
It happens that, given our usage in the Ausnet distribution area of Victoria, we spend about $350 per annum on electrical energy (there is also the supply charge which doubles this figure, but if you are connected to the grid you can not avoid this cost) so across a 10 year period the rough savings would be about $3500 which is less than the battery cost. At that point I advised the rep that no I wouldn't like to go any further and no I am not going to pay a deposit, thanks for your time.
Since then I've had a chance to crunch the numbers with a little more accuracy - I made the following assumptions:
1. There would be no battery deterioration - which isn't the case as my research suggests that at the end of 10 years you can expect 80% of the original capacity.
2. The battery would store and return it's full capacity each day after sunset but before 11:00 pm - also not true owing to overcast days and nights where the residence is unoccupied.
3. Energy costs would escalate - here I calculated the 10 year end point cost based on increases per year of 2.5% and achieved an average figure across the period.
Based on this the savings would be $3150 - not looking good - and it is going to be a lot less owing to the factors in 2 and 3 immediately above..
At the average energy rate I calculated $6000 approx. buys 20.855 MWhr or 5.7 kWhr per day (almost twice the battery capacity)across the 10 years which equals about $1.63 per day.
This looks to me like a "clever" marketing scheme dressed up to look like a "Bargain" if you get to be lucky and are selected to take part in the data gathering process.
And it carries another danger: you will be giving a company over which you have no control access through you router/modem fire wall as a part of the data gathering process.
You may care to spread the message - non attributable.
Cheers