Homeowner Blog

In light of the recent news, the idea of being grid independent with your own power cut protection has become a lot more attractive. 

We have had a number of customers interested in upgrading their solar PV or battery systems to protect them from power cuts. As we mentioned in a previous blog, a solar PV system alone will not protect you from an outage. With no batteries, if the power goes out, your PV system will switch off. This is a safety mechanism so that you do not discharge any excess PV energy to the grid and seriously injure someone if they are working to repair the grid near your house!

Even if you have a battery, some of them will not be able to island your property from the grid, which is the crucial step needed to have a backup system. Batteries need to follow strict DNO regulations to operate during a power outage as well, and will always need prior grid permission before installing.

At the end of January, thousands of homes local to us across Reading, Bracknell and Basingstoke suffered power outages for an average of 3 hours. This past week, Storm Ciara denied over 500,000 of us access to electricity. And last August the country was hit by the worst blackout in a decade, affecting hospitals, trains and over a million people. 

Now that Christmas is less than a week away and the new year is just around the corner, it only seems right to reflect on what has been quite an eventful year for the solar and renewables industry.

We’re entering a period of dramatic change for the energy sector. From smaller independents breaking the hold of the Big 6 and consumers generating their own solar power to dynamic pricing plans and smart homes.

The latest innovation is one that combines all of these: Octopus’s Tesla Energy Plan.

Yesterday I had my own modest version of a Victor Kiam moment.

If you are too young to remember Mr Kiam, spend 30 seconds watching this…. Mr Kiam's famous line ‘I loved the shaver so much I bought the company’ was the cornerstone of a hugely successful 1979 advertising campaign.

Mr Kiam was swept away by the joy of a sharp shave. For me it was Tesla and the sheer passion with which they are pursuing their mission ‘to accelerate the world’s transition to sustainable energy’.

The long-awaited Powerwall 2 backup capability is ‘on the water’, with the first wave of deliveries expected in April.  There’s a two stage roll-out, based on the type of earthing system required. Stage 2 will be in August.

If you are familiar with the Powerwall system, you will know that the system consists of the Powerwall unit itself, which houses the battery and the inverter, along with a ‘gateway’ which provides remote connectivity.

The original gateway, ‘GW 1’, was a plastic fronted box providing remote connectivity to the system.

From April this will be upgraded to a new gateway, GW 2, a stylish frosted glass-fronted ‘mini’ version of Powerwall 2, measuring 380mm wide x 580mm tall x 127mm deep, and weighing 9.8kg.  It is IP55 rated, so suitable for outdoors, and can be padlocked to stop any unwanted access.

The main purpose of the gateway upgrade is to enable ‘backup’ capability so that the homeowner can still power their home in a power cut.

So confident is Tesla that all customers will want the new backup enabled system, that they are actually expecting to discontinue GW 1 altogether, even though GW 1 offers a lower cost entry point into the Powerwall 2 system.

Tesla has certainly done its research. According to the company, in the nine month period 18/6/18 – 18/2/19 there were 93,965 unique power cut incidents in the UK, typically lasting between 15 mins and 4 hours and impacting 2 million customers. Anyone with a solar panel backup system in place would be smiling now....

[Apparently there are 22,200  online searches for "Schadenfreude" every month in the UK.  I wonder if Mr Musk has checked that stat out ....]

With 11 days to go until Christmas, Michelle Obama has launched her bid to join Christmas bestseller lists across the globe, Simon Cowell et al have launched their usual bid for the Christmas Number 1 song slot, and the nation prepares once more to vote in the Strictly Come Dancing final tomorrow.

A similar end-of-year flurry is taking place in the home battery storage market, all with a view to turbo-charging the market in 2019.

In the last few weeks:

Four weeks ago, we compared the warranties of Tesla’s Powerwall 2, Powervault 3 and Pylontech.

This week, both Powerwall 2 and Powervault 3 have updated – and improved – their warranties.

Powervault has in fact changed the underlying chemistry of its battery and launched GridFlex^TM, but more on that next week…

For Powerwall 2 customers, the update is retrospective which is good news for our Powerwall 2 customers.

Now to the fine print….

When considering battery storage, the costs are vital. So let’s see how they stack up for two of the biggest brands, Powervault 3 and Tesla’s Powerwall 2. As a rough guide, for someone installing a battery as part of a solar system (thus with a VAT rate of 5%), the rough costs are as follows:

I have an abiding memory from secondary school of our chemistry teacher pressing ‘play’ on an old video cassette, and there, projected onto the screen at the front of the room, was a video made by what must have been a desperately struggling actor, dressed in yellow tights and a white coat, dancing on a lab bench and singing the 'Periodic Table song'.  

The video served two purposes:

• it put us off chemistry;
• it put us off acting.

At least it put me off acting. Kristin Scott Thomas attended the school a few years before I did, and clearly, it didn’t put her off acting (credits include Four Weddings and a Funeral, The English Patient, and most recently Winston Churchill’s long suffering wife in Darkest Hour ). No dancing on lab benches for her just to pay the bills.

To the video’s credit, more than a couple of decades later, I can still remember the first two rows of the Periodic Table. Of course I’ve never used the knowledge, until the advent of home battery storage.

Today, as the second in our series of blogs on Powervault 3, we are studying Lithium Ferro Phosphate (Powervault 3) vs  Lithiated Nickel Manganese Cobalt Oxide (Tesla Powerwall 2).

Don’t worry, ‘Studying’ is over-egging it. We’re looking at the differences from a home battery storage point of view...