How a Household with an EV and Electric Heating Saves Over 650 € per Year – Thanks to a Dynamic Tariff

A household with an electric vehicle and electric heating can save up to 653 €per year with a dynamic electricity tariff – without reducing consumption.

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That means:

• 40% savings compared to fixed comparison tariffs
• 53% savings compared to the German average price according to BDEW

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In this article, you’ll learn how these savings are achieved and whether you can benefit as well.

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Why this matters for you

Dynamic electricity tariffs are one of the biggest innovations in the energy market in recent years.

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Many people ask the same questions:

• Is it really safe – or am I taking a risk?
• Will I actually save money – or might I end up paying more?
• And if so: how much can I realistically save?

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This article answers exactly that – based on real consumption data.

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The example customer: A typical household

For this analysis, we look at a sample household:

• Electric vehicle (regular home charging)
• Electric heating
• Annual consumption: approx. 3,100 kWh

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This is exactly the type of household that is becoming more common. It also shows that you can benefit from dynamic tariffs even without a solar system or home battery.

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This household has neither solar panels nor a home battery – and still benefits from cheap solar electricity at midday.

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You could even say: as a dynamic tariff user, you’re tapping into Germany’s largest solar power plant. You benefit from the low-cost electricity of all solar systems feeding into the grid.

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The result: Actual savings

The difference is clear: With a consumption of 3,100 kWh, our example customer paid only 591 €for electricity in 2025, which corresponds to an average price of 18.67 cents per kWh.

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For comparison – with the exact same consumption, they would have paid more with other tariffs:

• SimplyFair by Ostrom: 726 €/ year
• Market comparison (Check24): 978 €/ year
• Average (BDEW): 1,244 €/ year

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= Savings: up to 653 €per year

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And here’s the key point:

• They did not use less electricity
• They simply used it more intelligently

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The advantage is also clear in percentage terms:

• 53% cheaper than the German average
• 40% cheaper than a typical market tariff
• 19% cheaper than our own SimplyFair tariff

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The real difference: When electricity is used

The biggest lever is surprisingly simple: Not how much you use – but when.

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The consumption data clearly shows: electricity usage increases when energy is cheap and drops during expensive hours.

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Typical real-life examples:

• The EV charges at night when demand is low and electricity is cheap. Or, as in our example, at midday when solar surplus pushes prices down.
• The heat pump runs more during cheaper time windows, using the building’s thermal mass as a buffer to maintain a stable indoor temperature.

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The result: same comfort, significantly lower costs.

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Electricity prices on the exchange fluctuate significantly throughout the day, depending on how much renewable energy is available:

• If demand can be covered by renewables → electricity is cheap
• If more expensive sources are needed → electricity becomes more expensive

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A dynamic tariff passes these prices on to you directly and transparently.

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So you pay:

• less when electricity is abundant
• more when it is scarce

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By intelligently shifting your consumption, you can take advantage of the cheaper hours. Many device manufacturers already offer this optimization directly in their apps.

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Or even better: connect your devices directly to the Ostrom app and let your EV, for example, charge automatically when electricity is cheapest.

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The key difference compared to traditional fixed-price tariffs is that you’re not just paying an average price – you can actively benefit from the cheapest hours.

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What about very high prices?

One of the most common concerns is: “What happens if prices suddenly spike?”

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Yes, this can happen. Individual hours with very high prices may occur, for example, when renewable generation is low and demand is high.

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However, two things are important:

1. These periods are rare and usually short. They have little impact on annual costs.
2. You can often avoid them. You’re not at their mercy – you stay in control of your consumption.

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Why traditional tariffs are often more expensive

With a traditional fixed-price tariff, you always pay the same price per kilowatt-hour, including risk premiums from the provider.

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In practice, this means:

• Cheap hours: you don’t benefit
• Expensive hours: you still pay your standard price

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If you don’t have controllable devices like an EV or a heat pump, a dynamic tariff is less beneficial because you can’t actively shift consumption. They can still make sense, but if you prefer a fixed tariff you can take a look at our SimplyFair12. Once you have controllable devices, you can switch to a dynamic tariff.

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How realistic is this in everyday life? (and how Ostrom helps)

The key question is: “Do I need to constantly manage this?”

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In short: No – especially not with the right tools.

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With the Ostrom app, you can connect devices like your EV or wallbox and automatically control when they run, so you always use the cheapest electricity – without daily effort.

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Many device manufacturers have already integrated similar optimization features into their apps because the benefits are clear.

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So you have multiple ways to automate your consumption without constantly changing your behavior. This makes dynamic tariffs easy to use in everyday life and allows more households to benefit from the savings.

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Who benefits most from a dynamic tariff?

Especially worthwhile if you:

• own an electric vehicle
• use a heat pump
• and most importantly: can shift at least part of your consumption

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Less suitable if you:

• have very low electricity consumption
• have hardly any flexible or controllable devices

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You don’t need a large solar system or home battery to benefit. Rule of thumb: the greater your flexible consumption, the higher your savings potential with a dynamic tariff.

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Does that mean I can’t benefit without large appliances?

Dynamic tariffs are especially beneficial if you have large consumers like an EV or heat pump. Without them, you can shift less consumption to cheaper times – but that doesn’t mean you can’t benefit at all.

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Here’s another example: a customer without such devices, consuming around 3,400 kWh per year.

• With SimplyFair:  1,068 €
• With the dynamic tariff: 1,013 €

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→ Savings: 55 €

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Compared to the BDEW average (1,341 €), the savings are even 328 €.

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This shows: even without controllable devices, you can save by shifting usage – for example, running your washing machine at midday.

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Conclusion: Same electricity, significantly lower costs

This case study clearly shows: saving several hundred euros is realistic.

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Without sacrificing comfort. Without using less electricity.

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And even without an EV or heat pump, you can still save a bit by shifting your consumption to cheaper times.

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The difference lies entirely in when you use electricity.

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Switch to Ostrom  and start saving. Switch now.

• Cost of an average tariff on Check24 as of March 12, 2026, for the sample customer’s postal code.
• BDEW: https://www.bdew.de/service/daten-und-grafiken/bdew-strompreisanalyse/

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