How Shelly smart control reduces your carbon footprint — with concrete examples

Demand flexibility at home — small action, big impact

A common thought is: “Why does timing matter if my total consumption is the same?”

This is where demand flexibility meets the reality of the power system:

• Not all loads can run simultaneously without relying on more expensive and dirtier generation.
• When consumption is shifted away from peaks (morning/evening spikes) to windy/solar-rich hours, the system becomes cleaner.

Shelly devices and predictive control (MPC) can automate this shift.

How do electricity emissions form?

Finland’s electricity mix is relatively clean on average, but:

• when demand is very high, more fossil generation is needed
• balancing power is often gas or coal somewhere in the Nordics/Baltics
• at those moments the marginal production is the dirtiest

In other words:

Moving one kWh away from a peak hour can reduce emissions more than saving one kWh during an average hour.

Example 1: a water heater and emission reduction

Assume:

• your water heater consumes about 3000 kWh/year
• without smart control, usage is random
• predictive control (MPC) + Shelly shifts 30–50% to cleaner and cheaper hours

If the emission difference is roughly:

• 150 g CO₂/kWh (peak) vs 50 g CO₂/kWh (windy night)
• difference 100 g CO₂ per shifted kWh

If 1500 kWh/year is shifted:

• 1500 kWh × 100 g CO₂/kWh = 150,000 g CO₂ = 150 kg CO₂ per year

That’s roughly comparable to:

• about 1000 km of driving a typical petrol car.

And that’s just one water heater.

Example 2: electric sauna and seasonal peaks

An electric sauna is a major load in many homes:

• 6–9 kW during heating
• many people heat it on Friday evenings when the grid is already stressed

Predictive control (MPC) can:

• suggest pre-heating earlier during a cleaner/cheaper hour
• limit simultaneous power with EV charging and the water heater
• keep the main fuse from overloading while smoothing peaks

Impact:

• every avoided peak reduces the need for fossil balancing power
• shifting even 200 kWh/year to cleaner hours can cut tens of kilograms of CO₂

Example 3: EV charging

An EV can easily consume:

• 2000–4000 kWh/year depending on mileage

Without smart control, charging often happens:

• right after work (evening peak)

With predictive control (MPC) + Shelly:

• charging is planned for cheap and clean night-time hours
• the car is ready when you need it

If 2500 kWh of charging is shifted with a ~100 g CO₂ benefit:

• 2500 kWh × 100 g = 250 kg CO₂ less per year

Combined with a water heater, you quickly reach hundreds of kilograms of annual CO₂ reductions for a single home.

Why automation is the key

Manually tracking prices and emissions is exhausting:

• checking data daily
• deciding the best times for each device
• constantly adjusting timers

Shelly + predictive control (MPC) can do this for you:

• fetch prices (and optionally emissions)
• optimize schedules
• execute control via Shelly without you needing to remember anything

That means:

• small emission reductions every day
• without constant effort

Summary: money and environment in one package

With smart Shelly control you:

• save money by shifting consumption to cheap hours
• reduce emissions by using electricity when it’s cleaner
• help the whole power system rely less on the dirtiest balancing generation

What feels small in one home scales massively when thousands of homes do the same.