Beware of Blended Payback: Solar Pays For Itself But Batteries Don’t Yet.

June 6, 2017 2017-06-23T15:44:05 by 57 Comments
a solar panel, a battery and a blender

We are seeing a lot of battery companies only quoting the payback of solar and batteries combined. But adding batteries makes payback worse. So always compare the payback of just solar.

I want you to know I have a great investment for you.  Believe me, it’s great.  I have all the best investments.  Trust me — it’s yuge!  If you invest in the Ronald Trump fund you will get an average return of over 4%.  I guarantee it!1  Just hand over your money and you’ll start making money!

What’s that?  You want me to actually explain what I will do with your money?  Trust me, you don’t want to worry your pretty little head about that!

What?  You do want to worry your pretty little head about that?  Alright then, what I will do is take your money and invest it in the Australian stock market.  Then each year I will take all the dividends and all the capital gains and I will reinvest half and I will take the other half in the form of $50 notes and burn them.  It will be great!  In 10 years you can have over a 50% return!

Wait a minute!  Calm down!  You say you don’t want me to burn half the money your investment makes?  I don’t understand why you are complaining.  You will still come out ahead! [Read more…]

Filed Under: Battery Storage Tagged With:

Tesla Says Powerwall 2’s Return Will Be 8-15%. Really?

April 11, 2017 2024-10-01T10:41:42 by 55 Comments
powerwall spruiker

Is it reasonable to expect a “8-15% return on investment” on a Powerwall 2?

Last month, Lyndon Rive, Tesla’s Vice President for Energy Products, stood up in front of a large group of people, including me, and promised the Powerwall 2 will deliver a return between 8% and 15%. [Read more…]

Filed Under: Battery Storage Tagged With: , ,

Is The Powerwall 2 A Good Investment?

December 21, 2016 2024-10-01T10:39:14 by 85 Comments
powerwall 2 and piggy bank

Will a grid connected Powerwall 2 beat a term deposit as an investment?

Update: read about the newly arrived Powerwall 3 in Australia

Tesla has announced the impending arrival of the Powerwall 2 at a promised price point that, on the surface, looks very compelling: $10,150 fully installed1, or  23c per warranted kWh.

It seems particularly impressive when you consider that in Sydney and Perth, time-of-use tariffs can go to 50c per kWh during peak periods.

That’s 23c for electricity from a battery vs. 50c for grid electricity. Surely that makes the Powerwall 2 a no-brainer investment for people on such a tariff?

I decided to look a little deeper into the economics of using Australia’s cheapest battery2, on Australia’s highest grid tariffs.  Unfortunately I found that high peak rates are not nearly as good for the economics of the Powerwall 2 as they seem.

Read on to discover why. [Read more…]

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An Off Grid Solar System Can Pay For Itself But Can’t Beat On Grid Solar

April 23, 2015 2024-01-25T13:23:07 by 22 Comments
Ronald's parents

Lot’s of folks are wondering if it is time to leave the grid.

Home energy storage has gained a lot of attention recently, and many people think making homes independent from the grid by using batteries to store electricity from rooftop solar is an idea whose time has finally come.

So will home energy storage soon be like rooftop solar in that it will pay for itself and be used in homes across the nation, or is it like a porn star?  Always coming, but probably not something you would actually want in your house.

To gauge its prospects I decided to investigate whether or not a household that is well-suited for energy storage could save money right now by installing an off grid solar system.  And entirely through good fortune and not at all because I am too lazy to bother doing real research, my parents just happen to fit into this category.  If they can’t save money by going off grid then probably no one can. [Read more…]

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How I got a $33 power bill with solar – even with a crappy 8c buy back rate

February 5, 2015 2019-09-16T11:35:08 by 173 Comments

Update: This post was written in 2015. It is still worth a read to understand how solar affects your bill – but if you want to browse all my recent bills you can do so here.

I got my quarterly electricity bill last week. It was $33. I was so happy that I tweeted AGL.

AGL’s reply is priceless:

I’m guessing AGL don’t get a lot of compliments on Twitter! I also posted a scan of my bill on SolarQuotes’ Facebook page:
[Read more…]

Filed Under: Solar Panels Tagged With: , , ,

How Much Will You Get Paid For Your Solar Electricity?

October 11, 2012 2017-07-28T18:36:20 by 7 Comments

Hint: It’s a bit more complicated than you might think!

By my reckoning 25% of people buying solar power systems want to save the planet as a priority. The other 75% want to save their bottom line and saving the planet is a nice side-effect.

I get a lot of emails saying: “Help! My bills are [insert large number here] dolars a quarter – what size solar system do I need?”

The answer to this question is quite longwinded – but if you want to understand whether a solar system is worthwhile for you financially – you need to understand this stuff! So I made a video to help explain. If you are considering buying a solar system I strongly recommend watching this:

[Note: Since I made this video the Victorian and QLD Feed In tariffs are no longer more generous than the rest of the country – they are both 8c per kWh at time of writing!]

[Read more…]

Filed Under: Solar Installation Tagged With: , , ,

Hybrid Solar Systems Part 3: Costs and Payback

April 27, 2012 2023-12-21T16:59:47 by 13 Comments
solar panels and a dollar sign

What’s the payback?

Note: This post was written in 2012 and is way out of date. For the latest payback figures  please read this page which is kept up to date >>> Are Solar Batteries Worth It

In my previous 2 posts I looked at the concept and design of Hybrid Solar systems.

The main conclusion of those 2 articles was that

a) Hybrid solar rocks!

b) But you gotta pay for it!

So the question this post will try to answer is:

How Much Extra Does Hybrid Solar Cost?

and bearing in mind the extra costs:

What is the payback of Hybrid Solar Compared To Regular Grid Connect Solar?

So let’s look at the cost of a quality 5kW system and then see what it costs to upgrade it to “Hybrid”. [Read more…]

Filed Under: Solar Installation Tagged With: , ,
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