Energy Monitoring Part One
I have a complex set of energy-related products that are all connected together. 46 solar panels, 13 inverters, 2 circuit breaker boxes, a stack of batteries, and a smart meter from the power company. Smart devices in the home, some that consume a decent amount of energy. Some of the stuff uploads data to the cloud, some can be accessed locally, some do both. The equipment was put in place in phases over the course of 5 years, and while I can monitor it, I want it on one dashboard instead of several different browser windows. This is a story about how I set something up.
History
You can review previous blog posts I’ve done on the complete solar project. However a quick summary is thus:
In 2015 or 2016, a smart meter was installed by my regional grid operator Oncor, replacing the old meter. This allowed for the installation of solar panels whose excess could be exported to the grid.
In 2017 22 300w Mission Solar solar panels with 11 APsystems YC-500 micro-inverters were installed, which were tied into the main circuit panel, providing power for most of the typical load of the day. It eliminated a good chunk of the electric bill. For monitoring, there is an APsystems ECU-3 version 4 monitoring device that can be accessed locally via Ethernet, but it is also capable of uploading data to the cloud. It obtains its data from the YC-500 micro-inverters via PLC (Power Line Communications). As the YC-500s and the ECU-3 are outdated and discontinued, as well as the cloud presence migrated to a different location, local access is the only way to get to the data.
In 2019 24 310w Mission Solar solar panels were acquired and hooked up to a SolarEdge SE6000H HD Wave inverter. This too was tied into the main circuit panel, covering the remaining house load with excess being uploaded to the grid in quantities that allowed for a large credit. It is being monitored via a SolarEdge device that uses Zigbee to talk to the inverter, and then this device uploads the data to the cloud via Ethernet.
In 2022 a 24kW HomeGrid battery system was installed with a very smart Sol-Ark 15k inverter. This allows for power during a power outage for critical items, stored power is used in the evening which historically had the most electrical load requirements, the critical items were wired up in a second circuit panel, and the Sol-Ark became the main source of monitoring via the cloud.
So monitoring has been taking place mainly via the Sol-Ark’s cloud presence, however since the panels have already been converted to AC power and are a part of the regular load, their exact levels are not tracked in Sol-Ark’s PV sections. Any time there is excess load over what the house needs, it shows up as negative house load. Solar panel power monitoring is part local access and part cloud presence. Accurate grid import tracking is via yet another cloud presence from the grid operators.
Needs
Monitoring is tedious. I take this whole green thing fairly seriously, but I want to be realistic about it as well. For example when it came time to get a new hot water heater, I did some research. To help with the decision I also needed to know some rather exact numbers to crunch so I’m not simply make a “green choice” but a choice that actually saved me money. I knew it would save some money but I had no idea how much, and knowing that exact amount could mean the difference between choosing one product over another, and could involve a hundreds or even a thousand dollars. I wanted to know exact energy saving amounts possible.
As some of my calculations involved collecting data during events like power and internet outages, I wanted monitoring that could function independent of all that if possible. I put together a list of things I wanted to meet.
Data collection and monitoring should take place locally and in real time.
Easy access to historical data.
A singular dashboard or monitoring system that I could access via multiple devices (laptop, phone, dedicated panel or tablet).
Only use cloud-based data as a last resort.
Phase One
I already used Home Assistant for controlling a number of lights and blinds on windows. So it made sense to use that as a singular dashboard. Right off the bat I first started by seeing what I could bring into Home Assistant by checking existing Home Assistant integrations.
There are two SolarEdge integrations - one for local access, and one for cloud access. Unfortunately the local access one will not work as the latest versions of SolarEdge inverter firmware disable local access. Therefore I used the cloud access integration, which works fine. With this, 24 of the 46 solar panels’ data was being fed into Home Assistant. Perhaps in the future I can regain local access, possibly via Zigbee, but for now I wanted its data in Home Assistant.
Grid data is accessible via the cloud, and I used the Smart Meter Texas integration. Setting it up was fairly painless, and it was interesting in that the usage amounts differ from what I was getting from the Sol-Ark and its cloud presence, as Sol-Ark was showing slightly lower totals. I’m relying on the Smart Meter Texas data as that is showing what value will be used by my power company’s billing calculation, and Sol-Ark doesn’t seem to add in its own electrical usage for managing itself and the batteries into its calculations. The Sol-Ark is rated for 90w of idle power, which works out to 2.16 kWh a day. Now considering the Sol-Ark is operating with a load part of the time, the differences in what the Smart Meter Texas integration is reporting and what the Sol-Ark is reporting makes sense. Hence my dependency on the cloud-hosted Smart Meter Texas data.
Even though I had already set up integrations for the Wallbox EV charger and the AO Smith water heater, I also started putting together a single dashboard as these were devices I wanted to track the usage of. I called the dashboard “Infra” as it was smart stuff I wanted to keep an eye on.
This left a gap with the 22 remaining solar panels and the Sol-Ark, as well as some of the other heavy hitters when it comes to electrical usage. These heavy hitters included the refrigerator, the dryer and the Daikin HVAC system.
The Next Phase
For the Sol-Ark, this will be rather interesting. I’ve purchased a pile of hardware which along with some specialty software to do all monitoring locally. I’m expecting the install to be rather tricky. It involves patching into the Sol-Ark and feeding the data into Solar Assistant. This is still just a more detailed version of the cloud presence, but if I can get that data into Home Assistant and combine everything together then it will be worth the effort, plus I’d be pulling in that data locally.
The monitoring of gas and water will be happening at a later date. There are few different applications I want to start monitoring, mainly out of curiosity, but also to help further control and regulate energy usage. I’ll start that work later on as well.
Conclusion (for now…)
As I am writing this, I am already working on a solution for the 22 panels. This is one where I am going to have to code things up to get it working. Fortunately the monitoring device is local with a simple web interface, so I don’t expect the coding to be too complex, it’s just I want to experiment into foreign areas with this part of the project as both a problem solving experience as well as a learning experience that could be applied to other future projects. More coming soon!