How to use a Home Energy Management System to charge your EV for less

Winter’s rolling in, and if you’re like most of us, the thought of skyrocketing energy bills sends a chill down your spine, even before the temperature drops.

Maybe you’re constantly playing detective, looking for better energy tariffs. Perhaps you’re jumping from one app to another trying to manage your home devices and optimise EV charging. Or maybe you’ve already given up — it’s all too complicated, you’ll just have to take the hit somehow…

What if we told you there was a way to get better results — without all the hassle?

It’s called a Home Energy Management System (HEMS). In this guide, we’ll explain exactly what it is and how it can help you take control of your energy usage, cut carbon emissions and expenses.

HEMS and the art of slashing your energy bills

A HEMS is a smart blend of software and hardware that serves as the control centre for all your home energy needs.

The hardware consists of electricity meters and sensors, and wired or wireless connections to your appliances, including your EV charger and (if you have them) solar panels and batteries.

The software communicates with the hardware to gather and analyse data, set preferences and schedules, and monitor and optimise how and when your appliances consume electricity.

Just like a nutritionist would look at your lifestyle, current diet, fitness goals, budget, and biological data to create the best diet for your needs and goals, a HEMS looks at your energy consumption patterns, electricity prices, weather, and a list of other data points to determine the most efficient and cost-effective way to use energy in your home.

How a HEMS plans your energy diet

With a HEMS, you won’t be throwing random ingredients into a pot and hoping for the best. You’ll have a Michelin-starred chef who makes sure every kWh consumed is worth its penny.

The system analyses a vast amount of data to:

Plan your meals (a.k.a. find the cheapest and greenest times to charge your EV and other devices)
Find the best deals for you (in other words, the most cost-effective tariffs)
Detect inefficiencies in your workout routine (a.k.a. your energy consumption)
Decide when to eat in or dine out (when you’ll gain more by using the electricity generated by your solar panels vs. from the grid)
Provide recommendations on how to reach your goals faster
Track and reflect your progress

The data HEMS looks at

Energy consumption: Similar to a fitness tracker that shows how many steps you’ve walked, a HEMS will monitor your historical and real-time energy consumption so that you can keep track of which appliances are on and off, which ones consume the most energy, and which might be malfunctioning and using more energy than they should.
Energy tariffs and peak usage periods: Keeping track of when best to switch on an appliance is exhausting. A HEMS takes this strain away from you. It will look at your energy tariff and usage data to determine when to increase or decrease the use of electricity, so you can minimise your energy costs and carbon footprint.
Weather forecasts: Just like you would want to know a thunderstorm is coming before planning up a BBQ, effective energy management needs to take into account weather patterns to determine when best to schedule appliances to run. This is particularly useful if you have solar panels and generate your own electricity or when you want to ensure you are only consuming green electricity from the grid.
Energy sources available: Using solar thermal, wind, or solar panels? Excellent. But how do you know how much of it you’ve got, when to use the energy produced, when to store it, and when to send “leftovers” back to the grid? This is only possible by looking at the full picture, including energy prices, the weather forecast, and your usage patterns to make a well-calculated decision.

Understanding your EV’s energy needs

Just like humans, every EV has its unique dietary needs and metabolism — how fast it burns energy and how much “food” it needs to keep going.

EVs vary in:

Energy sources (battery vs hybrid vs plug-in hybrid)
Range (How far it can travel with a full battery)
Battery capacity (The maximum charging speed compatible with your EV)
Charging speed available (slow vs fast vs rapid vs ultra rapid)

For example, standard chargepoints put out between 3.5kW and 7kW of power. That means you’ll need between four to eight hours to fully charge your EV (the exact time depends on the size of your battery). You can usually count on a 10-25 mile top-up per hour of charging.

Once you know your EV’s diet, you can tell your HEMS when to “feed” it (or, in the case of a top-level HEMS, it will be able to determine that on its own).

How the extended family of appliances fits in

We probably wouldn’t be too far from the truth by saying that your EV isn’t the only thing feasting on your home’s energy menu. There are the occasional hungry snackers — an oven, a dishwasher, a tumble drier, a washing machine, and a merry crowd of always-on appliances — your fridge, your freezer, broadband router, and so on.

If you really want to cut down your energy costs, you’ll need to consider the role of this extended family of appliances in your energy consumption. For example:

What’s the average electricity consumption in 24 hours?
How big a difference does the dishwasher and the washing machine make when they join the table?
What are your options for limiting the negative effects on your budget?

This is where a HEMS makes a lot of difference. The system not only takes care of data gathering and calculations for them, but also makes sure everyone in the family gets their share without breaking the bank.

How to spot a good HEMS

The non-negotiables

There are a few non-negotiables that should come with any Home Energy Management System you choose.

Device compatibility: For any of this to work, your HEMS needs to be able to talk to all the appliances in your home, not just a select few. It needs the capability to monitor, control, as well as optimise all the devices in harmony. Otherwise it’s like getting a sports car but never taking it further than driving around the block.
Real-time monitoring: Imagine being at a football match and the scoreboard is 20 minutes behind. Unthinkable, right? Your HEMS should offer a detailed, real-time overview of how much energy you’re consuming, when, and how — any time you need it.
User-friendly interface: Look at the web and mobile platforms the HEMS comes with. Are they easy to navigate? Are all the data insights you’re looking for there? There’s no point gathering data if you can’t find, manage, or understand it without taking a course.
Good level of control: While the idea of the HEMS is to increase energy- and cost-efficiency with less time investment on your part, it should still give you the possibility to connect and control its settings. That includes manually turning appliances on and off, adjusting timers, changing your EV’s charging schedule, and so on — from any device.
Integration with renewable energy sources: Even if you don’t have solar panels today, you may choose to install them tomorrow. Your existing HEMS (and EV charging setup) shouldn’t stand in the way — or cause you to double the investment because all of it needs to be changed and reinstalled. There are HEMS solutions that are compatible with renewable energy sources out of the box.
AI-powered analytics: With so much data on your hands, AI is no longer a luxury. It’s a necessity. There are HEMS that can connect to your EV’s charger and understand your specific circumstances, needs, and goals (financial as well as environmental). Without AI, you’re just looking at a bunch of nice charts and data points without exploring all the opportunities they present (or spending hours on manual data gathering and calculations to do so).

The “highly recommended”

While you can get a very decent deal with the features described above, there’s one more thing that can really take your cost-efficiency to the next level — an AI-powered personal energy management assistant.

Imagine not just looking at data insights but having someone to:

Deliver personalised recommendations for higher energy efficiency
Choose the best tariffs and the cheapest EV charging times for you
Compare and advise on the best solar power solutions for you
Ensure you’re making the greenest energy choices, based on your personal goals
Automate energy management for you, while allowing you to make adjustments and exceptions when needed
Know when it’s more cost-efficient to store the solar power generated for later use (vs sending it back to the grid) — and act accordingly without requiring your interference

(Hint: That’s what it’s like when you’ve got Powerverse Vesta on your side.)

Whichever HEMS you decide to go with, we do recommend that you have one. It will save you hours of research and calculations, non-stop jumping between apps of all the smart devices in your home (the EV, the EV charger, the heating system, we could go on…), and, importantly, help make sure you do get the best deals in the market.

About Powerverse

At Powerverse, we’re experts in solar panel systems, EV chargepoints, and smart energy management systems that help you run your home and EV on clean and cost-efficient electricity.

Want to find out more? Get in touch to speak to one of our experts!