With a smart energy management system — home automation — you can save up to 30% on your energy bill. Not by using less, but by using smarter. Your heating switching itself off when you leave. Your washing machine running when electricity is cheapest. Your home battery automatically charging during periods of negative electricity prices.
The good news: you do not need to renovate. Most smart systems are wireless and can be installed yourself. In this article I explain which options are available, what they cost, and how much you can save.
What Is a Smart Home Energy System?
A smart home energy system — also known as a HEMS (Home Energy Management System) — is a central controller that optimises your energy use. The system monitors:
- Your energy prices (hourly rates with a dynamic contract)
- Your solar panels (how much electricity you are generating)
- Your home battery (when to charge/discharge)
- Your appliances (when your washing machine, heat pump, or EV charger is best to run)
The result: you use energy at the cheapest moment and store it when prices are high.
How Much Can You Save?
| Measure | Saving per year |
|---|---|
| Smart thermostat | €100 – €200 |
| Smart lighting | €30 – €60 |
| Smart plugs (standby killers) | €40 – €80 |
| HEMS + dynamic contract | €200 – €400 |
| HEMS + dynamic + home battery + solar panels | €500 – €900 |
| Total (everything combined) | €500 – €1,200 |
The exact savings depend on your consumption, your contract, and how many devices you control smartly. The 30% saving applies to a household that implements the full stack: smart thermostat + HEMS + home battery + solar panels + dynamic contract.
Which System Suits an Existing Home?
When renovating or retrofitting an existing home, you do not want to open up walls. Wireless systems are the logical choice.
Protocols Compared
| Protocol | Type | Advantage | Disadvantage |
|---|---|---|---|
| Matter | Wireless (new universal standard) | Works with all brands, future-proof | Not all devices available yet |
| Zigbee | Wireless mesh | Reliable, large range of products, energy-efficient | Requires a hub |
| Z-Wave | Wireless mesh | No interference with Wi-Fi | Smaller product range |
| KNX | Wired | Most reliable, professional grade | Expensive, requires wiring in walls |
| Wi-Fi | Wireless | No hub needed, easiest installation | Loads your network, less reliable |
Recommendation for existing homes: start with Zigbee or Matter. Both are wireless, affordable, and suitable for DIY installation.
Hubs and Platforms
| Platform | Best for | Hub price |
|---|---|---|
| Home Assistant | Advanced users, maximum control | €50 – €150 (own hardware) |
| Homey | Beginners, Dutch product | €200 – €400 |
| Apple HomeKit | Apple users | Free (Apple TV/HomePod as hub) |
| Google Home | Google users | €30 – €100 (Nest Hub) |
| Amazon Alexa | Alexa users | €30 – €60 (Echo) |
What Does a Smart Home Renovation Cost?
Starter Kit (DIY)
| Component | Costs |
|---|---|
| Smart thermostat (Tado, Netatmo) | €150 – €250 |
| 5x smart plugs | €50 – €100 |
| Hub (Zigbee/Homey) | €50 – €400 |
| Smart lighting (5 bulbs) | €75 – €150 |
| Total starter kit | €325 – €900 |
Complete Energy Package
| Component | Costs |
|---|---|
| HEMS system | €200 – €500 |
| Smart thermostat | €150 – €250 |
| Home battery (10 kWh) | €5,000 – €9,000 |
| Smart plugs + lighting | €125 – €250 |
| Installation | €300 – €800 |
| Total complete | €5,775 – €10,800 |
Professional (KNX wired)
| Component | Costs |
|---|---|
| KNX installation (existing home) | €5,000 – €15,000 |
| Lighting, blinds, heating | €2,000 – €5,000 |
| Programming | €1,000 – €3,000 |
| Total professional | €8,000 – €23,000 |
Installing It Yourself: 5 Steps
Step 1: Start With a Smart Thermostat
The quickest win. Installation takes 15 minutes. A smart thermostat learns your patterns and switches off the heating when you leave. Saving: €100–€200 per year.
Step 2: Add Smart Plugs
Plug-and-play. Insert them between the socket and appliances with high standby consumption (TV, games console, coffee maker). Put them on a schedule or set them to switch off automatically.
Step 3: Install a Hub
A Zigbee hub or Homey connects all your smart devices. From here you can set up automations: “when the sun is shining and electricity prices are low, start the washing machine.”
Step 4: Link Your Energy Contract
With a dynamic contract (such as those offered by Tibber, Octopus Energy, or local dynamic suppliers) and a HEMS, you can automatically shift your consumption to the cheapest hours of the day.
Step 5: Add a Home Battery (Optional)
The biggest saving, but also the biggest investment. A home battery makes you less dependent on the grid and maximises the value of your solar panels.
Frequently Asked Questions
Do I need to renovate my home for a smart home setup?
No. Wireless systems (Zigbee, Matter, Wi-Fi) can be added without any building work. Only KNX requires wiring inside walls.
Is a smart home secure?
Yes, provided you use strong passwords and keep your devices up to date. Choose brands that release regular security updates.
Does it work without solar panels?
Yes. A smart thermostat and smart plugs save money even without panels. A dynamic contract with HEMS also saves money — you shift consumption to cheap hours.
Can I install everything myself?
The starter kit (thermostat, plugs, hub, lighting) is entirely DIY. For a home battery and HEMS integration, a certified installer is usually required for the electrical connection.
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