So – we have chosen our batteries from Leoch, selected the electric engine and generator from Vetus and decided to go for 10 solar panels from Photonic Universe. However, there is still one very important “piece of the puzzle” to be solved and that is the energy management system.
If we refer back to the Electric Serial Hybrid drawing, you will see a component simply referred to as “Battery Charger”. This made the diagram simple, but hugely under valued this key component in the system.
We deliberated on the best name for this component, or what in reality is a series of components, and finally christened it; The Energy Management System (EMS). This post will endeavour to describe what the EMS is and which manufacturer’s components we chose.
Let us start by expanding the Electric Serial Hybrid diagram, focusing on the “Battery Charger” section and at the same time detailing the components we have already decided upon.
As you can see, energy is received from any of the three sources on the right side of the diagram and the first thing the EMS has to do is decide which is the best energy source to charge the batteries.
This involves monitoring the sources to see if we are plugged in to the shore supply, checking if the generator is running and also managing the solar panels. When there are AC “mains” power sources available the EMS will use its own battery charger to charge the battery and if no AC sources are available, then the MPPT controller will take over the battery charging, sunlight permitting.
In addition, the EMS has to manage the AC power on the boat, switching either of the two AC sources through to the boat’s AC sockets or if neither are available, using its own inverter to generate AC power from the DC power of the batteries.
Finally the EMS must supply all of the DC “battery” supplies required, which on “Old Nick” will be a 48v for the engine and inverter, 24v for most utilities and 12v for any equipment that is 12v only.
So the EMS for “Old Nick” will look like this…
I am sure you cannot miss the amount of “blue” in the diagram and many of you will have guessed that the equipment for our EMS will be coming from Victron Energy, the very popular Dutch manufacturer of energy solutions for mobile, remote and “off grid” installations. Thousands of UK canal boats have one or more Victron products and they are generally regarded as the leading brand in this market sector.
What is missing from the diagram above are the data connections between the Victron units. One of the strengths of the Victron products, is their networking and interfacing capabilities. The Quattro Charger/Inverter, MPPT controller and two smart shunts, all talk to each and provide a complete picture of what energy is being used/generated and where it is going to/coming from. They even do a smart bus bar, which would have been nice to have, but I had to keep one eye on the budget!
One very important device that is not shown in the EMS diagram, and in fact is not needed for the EMS to operate, is the latest Cerbo GX box, that is the “icing on the cake”. This compact, unassuming box connects to all of the devices and allows you to monitor, control and configure the EMS. This is all done through a simple wireless web interface, that you can view on your phone or tablet’s web browser – no special app required.
What the Cerbo GX will also allow us to do, in conjunction with Ortomarine’s, powerful and intelligent Touch Screen Controller, is allow the EMS, plus other important equipment and services to be centrally displayed, monitored and controlled on a dedicated colour touch screen. In addition, all of the data can be automatically uploaded to the cloud for remote monitoring and analysis.
Aside from our own personal interest, we hope that this cloud data (when published) will give Vetus feedback on the power usage and performance of their new E-Line engine, whilst also providing “real-life” data for anyone wishing to follow in our footsteps and make the jump to electric propulsion.