Replacing 20 year old Passiv Systems setup (heating & solar panels)

anotherbob

Our 3 bed semi's heating, hot water & solar panel array is controlled by a Passiv Systems setup which is almost 20 years old. It was installed by a company called PV Solar which I believe no longer exists.
It's been reliable and it does all we need but I'm conscious that some components might be expected to fail at their age and I'd like to pre-empt such a happening!. The Passiv Systems Android app works fine as a heating controller and It shows the performance of the solar panels. 
I'd like some advice on what sort of setup could replace it without losing any of the functionality.

QrizB

Are you receiving FIT payments for your solar PV system? If you are, you need to be careful what changes you make to the system. Do the wrong thing and you could lose the FIT entitlement.

Can you tell us more about your system, what it does and how the components interact?

I think there have been one or two previous threads about Passiv Systems, but search isn't cooperating right now

anotherbob

Thanks for your response. I must correct the "20 years old" assertion. The system commissioning date was 26/10/2011. We receive FIT payments at 90 day intervals. There are 10 panels and the generating meter is in the garage.
Information from the Panels can be seen via the Passiv Systems Android app and via a web link to passivliving.com on my PC. 

Our heating and hot water are powered by a gas boiler and controlled by the Passiv Systems app. There is a mains powered remote control which we used to use before the app was introduced.

The Passiv Systems "hub" is connected to our router by LAN cable.

QrizB

Ok, so the PassivSystems kit reports on your solar PV system but doesn't actively control it? But you can control your gas boiler via the PassivSystems app?

Unless you're a tinkerer and want to get involved with eg. Home Assistant, I don't think there's a one-stop shop for everything you're looking for. Smart heating controls are pretty commonplace, with Hive and Nest being the two big names but there are more options than those. Monitoring your existing solar PV might need something like OpenEnergyMonitor; there are a few users on the forum who can give more details if needed.

When you come to replace your solar inverter (you're likely to need to do this once or twice during the life of the system) you can think about getting an internet-linked one that will give you monitoring info via a website or app, a bit like your current setup does. All but the cheapest inverter models appear to include this option now.

I'm going to tag @FreeBear and @matt_drummer who both have smart homes and might be able to share their experiences!

Petriix

People may tell you that you can't alter your system without losing the FIT payments but, that's not actually true. The reality is that any changes must be agreed by your FIT provider and you may (likely will) need permission from your DNO to increase your export limit. And, crucially, you will have to ensure you retain an accurate generation meter.

In practice you would be able to replace the entire system with upgraded components but you would only be paid the FIT generation payments for the original proportion of your generation. Say you double the size of your array from 2.5kWp to 5kWp, your generation payments would be based on 50% of your future generation.

If you get a battery then I strongly recommend getting a separate AC coupled inverter for it rather than going for a hybrid inverter. This makes it easier to separate generation from battery output. The alternative is getting a new meter which can measure both in, out and net energy flow however this is a vastly more complicated arrangement with the potential for confusion with your supplier. 

Going for a separate inverter for the battery would potentially make it easier to charge it from the grid with cheap overnight electricity and export when it's more lucrative. You would almost certainly want to go to metered export payments so as to benefit from the generous rates currently available but this is contingent on having a cheap method for heating water (such as gas, overnight economy 7 or similar electric or a heat pump etc.). 

FreeBear

QrizB said:Unless you're a tinkerer and want to get involved with eg. Home Assistant, I don't think there's a one-stop shop for everything you're looking for.

I'm going to tag @FreeBear and @matt_drummer who both have smart homes and might be able to share their experiences!

You picking on us again

Home Assistant would probably do everything that @anotherbob wants. But it is a very steep learning curve and opens up a huge rabbit hole - With the right hardware, it could certainly control the heating and record data on just about everything. No need for an app, as you can access everything through a web browser (there is a HA app but I've never used it).

anotherbob

Thank you for your thoughts.
@Petriix I'm not considering alterations to the solar panel system, I just want to consider how I might deal with the potential failure of the Passiv components which currently monitor it.

@FreeBear Your references to "steep learning curves" and "rabbit holes" are enough to deter me from Home Assistant.

@QrizB I wonder if it might be possible to separate the heating control part from the solar panel monitoring and leave the Passiv setup to continue with its solar duties, but have a new separate system to control heating and hot water?

Grebulan

I am in exactly the same position, with a PV Solar system commissioned at very nearly the same time. Our desktop controller has been playing up and I exchanged emails with PassivSystems, who manufactured it. 

Basically, all the components of the system are not only out of production, but also out of stock. This means that if anything fails completely, it will be curtains for the system. Apparently the PassivSystems protocols are proprietary so no one else make compatible kit. 

The PassivSystems support was great, even turning on a couple of missing features missing from the iPhone app, however even he had to say that our system was obsolete and that the only future was with the likes of Nest or similar. 

Ho hum!