Renewables and Energy Technology

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Wind turbines, solar panels, home battery storage - if it's discussion about renewable energy you're after, you'll find it here.

When will AGL launch a customer Energy storage solution sizing and economic modelling calculator?



Hello All, yesterday I received correspondence inviting my family to register for AGL's upcomming Energy Storage Solution information.


I have three key questions:


  1. When will AGL launch a customer Energy storage solution sizing and economic modelling calculator?
  2. What Solar systems can or can't AGL's proposed solution be tighly integrated with - and are any integration limitations for technical or commercial reasons?
  3. Will you Energy Storage Management solution allow charge up from both Solar and Off-peak grid to allow for load displacement during peak charge times?

Many thanks,




AGL Employee

Hi Matthew,


The battery will be able to be used with a range of solar systems, whether they have been installed by AGL or not, and will work with solar and grid electricity. It might be a good idea to get in touch with one of the specialists at AGL? PM me if you’d like me to pass on details.


Further info will keep coming as we work with different battery suppliers. It’s an exciting time in the industry!






Thank you for your response to some of my questions (none of part 1, most of part 2 and all of part 3).


So to re-state my first question - with a worked example - when should a ROI calculator be available? 


From my daily usage data I could tell AGL today that I use 3.5 kWh peak and 4.1 kWh shoulder which totals 7.6 kWh daily ever day, and I could replenish this using excess solar each and every day for 365 days a year so its easy to calculate annual savings as:


annual savings = cost of peak and shoulder not used - loss of reduced solar fed to the grid


   365 * [(3.5 * $0.56) + (4.1 * $0.21)] - loss of solar fed to grids

= 365 * [ $1.96 + $0.86] - 365 * [7.6 * $0.08]

= $1,029.30 - $221.92

= $807.38


Now actually the savings are a bit less than this becuase there is no peak rate feed Saturday or Sundays so for 52 week * 2 days I am only off setting

52 * 2 * [3.5 * ($0.21 - $0.56)] (should not peak rates should have been used above)

= - $127.40


So my annual savings would be reduced to $807.38 - $127.40 = $679.98 or roughly $680 per annum...


So my question for part one is if that is a typical usage case - on a ten year maximum life solution - when will I reach payback of purchase price? Year 3, 4, 5, 6 or later?  You can see if AGL cost their 7.6 kWh solution above $6,800 it has no economic value to me and considerable performance risk.  If they priced it at half of this then pay back is in year five and there is considerable perfomance risk that is all born by me the owner. 


That was the heart of Part one above - noting this assumes no deterioration in the storage solution over time, and ability of the solution to intelligently disperse the power per a controlled plan for shoulder and peak use each day - plus several other factors.  So Ideally if I want at least a 20% ROI - I want purchase payback by year 4-6 ideally!


* * * * *


Point 2 of the original question asked about close, tight integration between solar production, grid demand and storage technology.  I am sure all the systems can interface - but do all three systems intergate seamlessly under an intelligent energy management controller.  So for example a system that tightly intergates and is web enabled would be the Enphase system - it has intelligence built in and complete integration between solar production, storage management and grid consumptions.


Is the AGL developed control system for your storage powerful, user configurable, intelligent and do the achieved results of what is occuring between solar production, grid consumption and storage power in/out available to the residential owner online in near real time (at least every 15 minutes) every hour of every day?


Many thanks if you can answer these questions!




Actually thinking more about AGL stating the Storage can be charged from the grid - this has rather interesting possibilities - so long as you mean the system can be charged from the off peak grid to be used in either the shoulder or peak periods.


1. Is this the case - did you mean AGL will allow storage systems - any storage system - or only their own - to be re-charged over night from the grid?


In this case the full 7.6 kWh for some folk may be able to be used in the morning, re-chearged from Solar excess during the day - and utilsed in peak period load off set during the afternoon / early evening.  This means you could charge and discharge the batteries fully twice per day - every day.  Meaning the 5,000 guaranted cycles will occur late in year 6 of the systems hoped for 10 year life! In which case you would want to get full ROI before year 6!


2. Re-doing the sums - 365 days a year, 250 days with peak rates evening and shoulder rates mornings, 115 days with shoulder rates morning and evening, full charge and dis-charge of the system per annum, gives


Mornings - charged by off peak grid   = [365 * 7.6 * ($0.21 - $0.11)] = $277.40 + Evenings =[250 * 7.6 * ($0.56 - $0.08)] + [115 * 7.6 * ($0.21 - $0.11)] = $999.40


Totalling $1,276.80 theoretical maximum savings per annum for 6.8 years (5,000 cycles) - presuming:


i) by cycles you meant 5,000 full cycles from 100% charge down to 0% discharges - Lithium Ion doesn't like this - most off grid users of Lithimum Ion from memory have to keep from 20% discharge to 80 recharge to meet the 5,000 cycles they are warranteed for (with year of year perfomance losses occuring


ii) The sytem can only at max deliver 2 kW per hour - so in peak most solar may produce until 5pm on average so you have at best

0.6 kW needed from 4pm - 5pm

1 Kw needed from 5 - 6pm

2 kw needed from 6- 7pm

2 kw needed from 7 - 8pm


So I would model only 6 kW useable on a maximum load afternoon (which may be Summer A/C 90 days and half the days of a year when a large electric oven might be used to cook food in the evenings) - so estimate 270 days a year when the full evening load can be used (5/7 of these in peak days) so about 192 days


Factor these elements in and you get an saving per year of around $800 - $900 over a six+ year life - which is in line with all the many other storage solution economic models I have seen for storage solutions on the market at around this size!


Can you please respond to all these points in detail please so everyone can share AGL's thinking.  Many folks on Green Tech forums are interested in this thread!


Also please do confirm - will AGL let all storage solution providers charge their systems from the grid at off peak rates over night to run their house or charge their electric car using off peak rate energy at the current off peak rate?


Many thanks,




Hi Matthew, 


It’s great to see someone so engaged with the distributed energy revolution. I've been in touch with Ed, our Energy Storage Lead, and he's given me more info to respond to some of your questions.


First off; yes, absolutely you will be able to charge from the grid to take opportunity of low off peak tariffs. I’d also like to give you some more information about the AGL Power Advantage battery. The first AGL battery will be able to discharge at 3kW, it can charge at up to 4.5kW from solar or 3kW from the grid. Later on we will have offerings with higher charge and discharge rates. You also mention the number of cycles, one cycle is one charge and discharge so 5000 cycles, at 365 cycles a year, will give you over 13 years of service. You are quite right that Lithium Ion batteries, like all batteries, do better without 100% cycling so the first Power Advantage battery will be limited to 80% depth of discharge.


We will be launching some modelling and benefits calculators very soon. The first people to see this will be these tool will be those who’ve signed up for AGL Power Advantage at:


Have a great weekend




If I've helped at all, a Kudos would be appreciated 🙂


Thanks Lauren, et al,


That's some helpful information there for me to digest.


So to my question - will AGL allow all providers of Storage solutions to re-charge their batteries over night from the grid at off peak rates - or will you restrict this to only your provided storage solutions?


Many thanks,