Life, the universe, and Redflow

Today Redflow announced the appointment of John Lindsay as a non-executive director of Redflow Limited. John has deep skills and experience around technology and technology related business matters. He is, to use a favourite phase (for us both), ‘smart and gets things done’.

Its worth appreciating that John has specific expertise and experience in precisely the realms that Redflow needs. I sent John over to Brisbane when I originally invested in Redflow, to help me assess the technical merit of the technology. He, like me, has been a shareholder in Redflow ever since.

In addition to being a great businessman, John is also a technology geek at heart (as am I). He has been an active member of the electric vehicle and renewable energy community for many years. His daily driver is electric (as is mine) – of course. He knows which end of a soldering iron is the hot end.

His idea of a fun weekend hobby is (literally – and recently) to have set up a D.I.Y. solar and battery offgrid system in his own garage to charge up his electric car from renewable energy because… he can (and because he knows how to).

His appointment frees me up to transition my own head space in the Redflow context totally into the technology around making our battery work in the real world. Doing that stuff is what I really love about being involved with Redflow. I love helping to make this amazing technology sing and dance smoothly for real people, solving real problems.

It was just the same at  Internode – the company I spent more than two decades running. The ideal situation is to do things in business because you’re passionate about it. In the words of Simon Sinek: People don’t buy what you do, they buy why you do it.

I care about Redflow because I believe that Redflow’s technology can genuinely help to accelerate the world’s transition to renewable energy as a replacement to burning things to make electricity. Its really that simple.

The technical lever I designed, to help Redflow to move this particular part of the world, is the Redflow Battery Management System (BMS). I am very proud of the great work done by the technical team at Redflow who have taken many good ideas and turned them into great code – and who continue to do that on an ongoing basis.

So… while there can be a natural tendency, when looking at this sort of transition, to wonder whether my leaving the board (given how influential I’ve been at board level in the last few years) is because something ‘bad’ is happening, or because I don’t like it any more, or because I don’t feel confident about things at Redflow, the reality is precisely the opposite.

My being happy to step back from board level involvement over the next few months is the best possible compliment that I can give to the current board, lead by Brett Johnson (and now including John) and to the current executive (now ably lead by Tim Harris).  

I’ve put my money where my mouth is, to a very large extent, with Redflow. I am its largest single investor – and I have also put my money down as a customer, too, in my home and in my office.

At this point, I’m happy to note that we are seeing great new batteries turning up from our new factory. We are on the verge of refreshing our training processes to show our integrators – and their customers – how far the BMS and our integration technology has come at this point (and just how easy it all is, now, to make the pieces work). We are looking forward to the integration industry installing more of our batteries into real world situations around the world again – at last.

We do this with confidence and we do this with eagerness.

I am proud to be a shareholder in Redflow and I look forward to the next chapter of this story.

The Role of Flow Batteries in Dispatchable Renewable Energy Grids

At the Australian Energy Storage conference held in Adelaide, South Australia on May 23-24 2018, I delivered this keynote address about the role of flow batteries and other energy storage technologies in the context of building an energy grid with renewable energy in the majority and with “Baseload” generation on the wane.

The core thematic question I posed was this: Is a future grid with large amounts of renewable energy storage necessarily using Lithium-Ion (or other, otherwise conventional) battery systems for the majority of that large scale energy storage – or are there better ways?

A specific underlying aspect of that conversation is about environmental impact – around the notion of ‘environmentally friendly’ energy generation and storage being a notion that must factor in the ultimate environmental impact for each storage technology and not just its up-front cost.

The video below is a recording of my address synchronised to the slide deck that I used.

The standalone slide deck is also available here: Hackett-Keynote-Redflow-AES2018

How Redflow Batteries Work

I often get asked to explain how Redflow ZBM2 flow batteries work – compared to conventional batteries – and how batteries fit into your life in a home situation.

An interview I did a while back with the delightful Robert Llewellyn explains those things.

So… If that’s a subject you’re curious about, and you’d like to spend 15 minutes learning the answers… this Fully Charged show about Redflow ZBM2 flow batteries explains it !

 

The Base64 Redflow Energy System

The Base64 energy system has been a fantastic learning experience for us in general and me in particular.

The system is built around a large Redflow ZBM2 battery array. We call these configurations an “LSB” (Large Scale Battery). It is charged with solar energy harvested from a large solar array (most of which is ‘floating’ above the staff carpark).

We deployed it first some time ago now, prior to having got so deeply experienced with using Victron Energy inverter/charger systems. At the time we (Base64) purchased a big custom industrial AC inverter that didn’t come with any sort of monitoring or logging system and no control system to drive it to interact properly with on-site solar.

All of the necessary energy system control, management and data logging technology comes ‘out of the box’ with the Victron Energy CCGX controller unit in a Victron installation,  so I imagined ‘everyone’ provided such things. Well, I was wrong about that.

The big industrial unit we bought came with nothing but a MODBUS programming manual and created a lot of head-scratching along the lines of… ‘now what?’. For some reason industrial scale systems are in the dark ages in terms of the stuff that Victron Energy have ‘nailed’ for the residential/SOHO battery market – they supply great, easy to use, easy to understand, effective and powerful out-of-the-box energy system control software and hardware (entered around their CCGX/Venus system). It also comes with an excellent (no extra cost) web-accessible portal for remote data logging, analysis and remote site system control.

Meantime, we were exercising our large battery ‘manually’ – charging and discharging it happily on a timed basis to prove it worked – but we were unable to run it in a manner that properly integrated it with the building energy use, for the lack of that control system in the inverter we had at the time. We didn’t want to write one from scratch just for us – that’d be a bit mad. We also didn’t want to pay someone else thousands of dollars to set up a third party control system and make it work – a major consulting project – just to do what the Victron Energy CCGX does on a plug-and-play basis at very low cost.

In parallel, and importantly – we also took ages to actually get substantial on-site solar operating at Base64 – and there wasn’t much point in driving the LSB in production until we did have a decent amount of on-site solar to sustainably charge it with.

To the latter point – we are in an massively renovated and reworked heritage listed building and I was unable to get permission to mount solar on the massive north-facing roof of the main building.

Instead we commissioned a rather innovative mounting system that has (at last) let us complete the installation of a big solar array that literally ‘floats’ above our staff car park on four big mount poles supporting what we call ‘trees’ – suspended metal arrays holding the solar panels up.

That system was commissioned and imported from a company called P2P Perpetual Power in California to suit our site. There are lower cost systems – but (by comparison) they’re ugly. We wanted it to be beautiful, as well as functional – because Base64 in all other respects is…both of those things.

It was worth the wait.

The result is (in my humble opinion) quite spectacular. We (at last) have a total of around 70kWp of solar on the site, though now I’m casting about to find some more ‘hidden’ roof spaces on the main complex where we might squeeze in just a bit more – you can’t have too much solar 🙂

In parallel, we pulled the LSB apart and rebuilt it using Victron Energy products and control systems, so that we could get a fantastic operational result and have optimal use of the solar energy to drive the building, charge the batteries, and support the building load at night – the very same stuff we do in houses with our batteries, just on a big scale – without facing a one-off software development exercise for the old proprietary inverter system we had been using.

Swapping the Victron Energy gear in has turned out far cheaper and far better than the bespoke software exercise would have ever been. It has also created a signature example of a large scale Victron Energy deployment running a decently sized multiple building site. I hope that this, in turn, may inspire more of the global Victron Energy installation community to consider the use Redflow battery technology at this sort of scale.

At the time of writing (January 2018), we have had 15 x ZBM2 batteries installed and running (150kWh total) for a few months now, with another 30 x ZBM2 units slated for delivery into the container later (its all wired up and ready for them). When installed, we will have a grand total storage capacity of 45 x ZBM2 = 450kWh.

There is 72kW of Victron inverters installed right into the container as well. We could have gone larger, but these have been ‘right-sized’ to the building demand at Base64, with demand peaks normally around 60kW and typical draw around the 30-40kW level when the building complex is in daytime operation.

Its all linked to a 70kW distributed solar array connected via multiple Fronius AC solar inverters. The main 50kW array is ‘floating’ above the staff carpark and the battery and the rest is distributed on other small, non-heritage, rooftop areas around the campus.

I’m thrilled with how well the system is working – its a monument to the last year or two of the Redflow BMS development work that the whole thing – at this scale – really is ‘plug and play’ with the Victron CCGX energy system controller and the associated inverter/charger equipment.

It is very satisfying to run an office in the middle of a major city that typically uses very little grid energy, that is resilient to grid faults, and that even still exports solar energy to the grid as well.

A subsequent step will be to interface with a grid energy ‘virtual power plant’ operator in the future, so that we can sell battery energy back to the grid during times of high grid demand. Every battery system on an energy grid has the potential to also become a grid-supporting energy source during peak load periods. The missing links there are software, regulation, and attitude – the technology part is easy.

Here is a little gallery of photos of the system that we’ve installed – click through them for a little more information about the system.

 

Internode NBN HFC using an Apple Airport Extreme as the site router

I installed an Internode NBN HFC service in an apartment a few months ago. It comes with a Huawei HG659 router, attached to the NBN standard issue Arris HFC cable modem.

I really don’t like that router. Its got some negative characteristics  – including it having a DHCP server that can get itself confused and conspire to keep handing out a conflicting IP address on the active network. I also much prefer using Apple Airport Extreme base stations for WiFi networking rather than the built in stuff in routers of that ilk (lets call them ‘low cost and cheerful’) – especially when I’m running multiple WiFi base stations (as is the case in the site concerned).

I’ve had great success in another site using Internode NBN via Fixed Wireless by just configuring the PPPoE client into the Airport Extreme and plugging that straight into the incoming connection from the Fixed Wireless NTD. That worked like a charm, and eliminated a similarly ‘cheerful’ router in that circumstance. However this simple approach just didn’t work on the NBN HFC connection – configuring the PPPoE client in the Airport Extreme and plugging it into the Arris HFC cable modem directly lead to no joy.

Each NBN ISP has some choice over how the HFC based NBN connection gets deployed to their customers.  Some digging turned up the data point that the Internode service delivered via the NBN-Arris HFC modem is implemented as two ethernet VLANs, with VLAN 1 delivering the bundled VoIP fixed line phone service and with the Internet service delivered over VLAN 2.

There is no way to configure the use of an upstream VLAN in the Airport Extreme – it expects the PPPoE frames to turn up natively (with no VLAN tagging).

Some more digging and the solution emerged, namely to keep the Huawei HG659 in the picture but use it merely as an ethernet VLAN decoder. In that role, its job is so simple that it can do it without losing the plot.

and… it works (yay!)… but there are – of course – wrinkles 🙂

The steps involved should have been this simple:

  • Configure the HG659 using its wizard to ‘connect with another modem’. This is what the HG659 uses as its description for bridging the incoming VLAN to the local LAN ports.
  • Keep the HG659 WAN port connected to the Arris HFC modem (obviously)
  • Cable the Airport Extreme WAN port into one of the LAN ports of the HG659
  • Using the Airport Utility on a Mac, configure your PPPoE account details into the Extreme (Internet tab, select PPPoE and then fill in the username and password, leave the ‘Service Name’ blank)

However, this is what I also had to do (all in the Airport Utility)…

  • The DHCP IP range configured into the Airport Extreme needed to be changed (at least, I needed to change it, to make things work – YMMV). I switched it from its default of the 10.x range, and instead set it to use NAT on the 172.16 range (Network tab, Network Options button, IP v4 DHCP Range drop-down)
  • I had to turn off IPv6 entirely to avoid an ‘IPv6 Relay’ error coming up (Internet tab, Internet Options button, Configure IPv6 drop-down set to ‘Link Local Only’).
  • Turn off ‘Setup over WAN’ to avoid an alert coming up on the Airport Utility and the base station light flashing amber (Base Station Tab, clear the “Allow Setup over WAN’ check box). The point here is to explicitly disable the capacity for the Airport Extreme to be accessed (by the Airport Utility) over the WAN path. That’s definitely something I want disabled. My only issue here is that I’m surprised this checkbox is actually on by default in the first place!

One more bit of collateral damage here is that I probably can’t access the free VoIP phone service delivered over HFC VLAN 1 and out via the analog port on the HG659. I don’t care, I wasn’t interested in using it in the first place. It may well be the case that some cunning manual configuration of the HG659 could make that work (too) – but I really don’t care about it – so I just haven’t tried.

The one silly thing left out of all of this is that I didn’t get rid of any physical devices in the process, so I have this conga line of three hardware devices between the cable modem wall plate and the user devices in the site – the Arris HFC modem, the HG659 (now as a VLAN 2 decoder box only) and the Airport Extreme (as the site router plus central ethernet switch to some downstream Airport devices).

Speed tests are just as good as they were already, with downstream rates testing reliably in the mid 90’s and upstream in the high 30’s – pretty darned good (especially through that crazy hardware conga line) on a 100/40 Internode connection. Importantly the issues I had with the HG659 router and DHCP are gone.

Other notes:

  • The Internode NBN HFC service is in fact deployed on TPG infrastructure, so the above should apply equally to a ‘native’ TPG NBN service too. This also explains why the IPv6 doesn’t work (sniff).
  • The VoIP service should be capable of still being used, perhaps with some custom configuration of the HG659, and I may try to find a way to make that work just for the sake of the challenge
  • A router such as a FritzBox which is capable of VLAN decoding on the WAN port should be able to be used to deliver the Internet service directly via the Arris HFC modem without using the HG650 at all (eliminating one device). Its also possible the FritzBox may be smart enough to support logging in to the voice service via WAN VLAN 1 as well … and that is something to try out another day…!

 


 

Postscript: There is another approach to the removal of the Huawei device from the critical path that has been pointed out to me on another blog – here. This won’t work with the Airport but it is a way to allow a Fritzbox or a high end Billion or another router with WAN port VLAN support to be used for the Internet path instead of the HG659, leaving the HG659 functional as well – in parallel – to provide the voice port service that is bundled in with the Internode NBN HFC service. The benefit here is for people who do want to use that bundled voice service while also removing the HG659 from the critical path in Internet access terms. While it does need yet more hardware (an ethernet switch) – its a really creative and effective answer that might be very helpful to others to know about!

Redflow ZBM2 deployment at Bosco Printed Circuits

A case study in complex energy system optimisation

Bosco Printed Circuits is the largest maker of Printed Circuit Boards (PCB’s) in South Africa. The production line at Bosco needs a lot of energy. The direct and indirect consequences of losing energy supply to the line are substantial.

Johannesburg, where Bosco are based, has significant issues with energy supply – both in terms of reliability and also (as a consequence) in terms of energy cost.

Like most businesses, Bosco already had an extensive solar array installation, which certainly helps with the economics of energy supply. The solar array is not sufficiently effective, is isolation, to address the complex challenges for the business in terms of supply cost and supply security.

Energy supply to Bosco from the grid utility is time-of-day based. The energy supply cost is very high during distinct morning and evening peak periods, to discourage energy use in those times. These peak time bands are periods of high energy requirement for Bosco. The are the times when the potential for grid failure is greatest and are also the periods when the consequences of grid failure for Bosco are the most severe.

Of course, these times (early morning, late afternoon) are also exactly the periods when the solar arrays can’t help, as they are outside of the solar peak generation periods.

Grid outages are expensive for Bosco. Not only do they result in lost productivity, but they also have further economic consequences in terms of partially produced PCB’s having to be scrapped when the production machines are halted without warning.

The Challenge

Bosco had a variety of business aims and objectives across their daily operating cycle that their energy system had to address:

  • To ride over transient periods of grid loss seamlessly using battery energy
  • To support the operation of the production line for an extended period (hours, not merely minutes) in the face of longer periods of grid outage, so that the company can keep working, using battery energy augmented with any available solar energy, for as long as possible.
  • In cases of a very extended grid outage (several hours), to allow the production line to be closed down with plenty of warning (at least an hour) from the point at which the shutdown decision is made.
  • To time-shift energy obtained from the low cost overnight off-peak period into the morning peak period (0600-0800), prioritising battery energy usage at this time in order to minimise the use of very expensive grid energy.
  • To also minimise afternoon peak-period grid usage by again prioritising the use of battery energy in this second daily period
  • To use the residual battery energy, harvested from overnight off-peak charging and from any excess of daytime solar power, to supply the background energy needs of the building into the evening.
  • To recharge the battery array again using off-peak power from midnight to 6am ready to commence the next daily cycle.

This need set required a battery energy system capable of consistent hard work and capable of daily 100% energy discharge, working in a hot environment, and without loss of output capacity over time.

The Solution

The solution uses 14 x Redflow ZBM2 batteries (140kWh) interfaced to a large array of Victron Energy inverter/chargers and a large solar array.

The system orchestrates this complex daily cycle of energy optimisation using the Victron CCGX and the Redflow BMS, to achieve the aims and objectives noted above.

Here’s a typical day in the life of this system, in terms of the sources of energy to run the plant:

Bosco Daily Cycle Example

Bosco Printed Circuits Energy Consumption

You can see the periods where the battery system energy (blue) is prioritised in order to minimise the use of grid energy during peak times. You can see the battery being fully utilised to supply energy during the afternoon and evening as the solar consumption falls away, and you can see the system recharging using off-peak energy again from midnight, ready for the following day.

You can use this Bosco Printed Circuits VRM Portal Link to see the live system running.

Bosco ZBM storage array

Bosco ZBM storage array (12 batteries shown – a further 2 were added later)

 

 

My home Redflow ZBM2 energy system installation

Here is some information about my home energy storage installation.

  • 2 x 10kWh Redflow ZBM2 zinc-bromide hybrid flow batteries
  • Redflow ZCell BMS
  • 2 x 5000VA Victron Energy inverter/chargers
  • 10 kWp solar panel array in four strings using 2 x SMA 5000-TL inverters
  • Victron Energy CCGX configured for solar self-consumption (Hub-4)

The Victron Energy Hub-4 software in the Victron CCGX optimises the system for solar self-consumption. In the presence of excess solar generation, that energy is applied first to the home loads, the surplus to charging batteries, and the surplus beyond that to export to the grid (if connected).

CCGX Solar Generation Example

High solar output period

When there is less solar generation than the home loads require, those loads are supported by the solar energy that is available, which is then automatically augmented with battery energy. The grid is used as required to further augment home demands as required (either when the peak load exceeds the battery inverter capacity or when the batteries are fully depleted).

The system allows the configuration of an adjustable reserve percentage of the storage battery energy to be kept in the batteries in case of grid failure. It also allows the system to be charge up proactively from the grid in periods of low grid energy cost or ahead of incoming bad weather that might increase the chances of a grid energy failure.

The system automatically reverts to off-grid mode if the grid is unavailable, including recharging the batteries from solar energy to help support loads in the home for extended periods during such outages.

The performance of the system is very good. On a sunny week, most of our home electrical energy is provided by direct and indirect (battery time-shifted) energy. Of course in weather conditions offering reduced solar energy, more grid energy gets used.

Like a home rainwater tank system, this system acts as an electrical energy buffer, doing the best it can to avoid the use of grid energy, and prioritising the use of battery energy first.

hackett-vrm-week-sample

System performance example during a good solar week

The system works very well indeed – and flawlessly from the standpoint of my family, who see a house that ‘just works’ – even when the grid doesn’t. We all appreciate seeing the house operating well into most evenings on time-shifted solar energy harvested during the day.

Hackett Home Energy Installation

Two Redflow ZBM2 zinc-bromide hybrid flow batteries

Note that this system doesn’t use Redflow “ZCell” enclosures because it pre-dates the existence of those enclosures. It was one of the earliest production deployments of Redflow batteries in a residential context.