Holiday rental energy costs: cut bills with technology

The 4 points where most energy is wasted

• Air conditioner: left running for hours with open doors or windows, or set to extreme temperatures (18°C in summer) that do not improve comfort but double consumption.
• Heating: radiators set to maximum while airing out the apartment, often because the guest does not know how to operate the valve or thermostat.
• Hot water: electric boilers left running even when the apartment is empty, especially older models without timers.
• Invisible consumption: towel warmers, decorative lights, dehumidifiers, and standby power for TVs and small appliances, which alone can account for 5% to 10% of the electricity bill.

Before spending any money, review your utility bills from the last 12 months and note three data points: electricity kWh, gas cubic meters, and average monthly cost. Compare them with your occupancy rate and the season. This tells you whether you truly have a waste problem or just normal consumption for your setup, preventing you from buying technology that does not solve the actual issue.

What to do before spending a single euro on technology

Not everything requires an investment. Some zero cost or low cost measures already reduce a significant portion of waste:

• Blackout curtains or solar film: applied to south or west facing windows, they reduce the load on the air conditioner in summer without altering the HVAC system.
• Budget mechanical timers (10 to 15 euros): installed on the electric boiler if you do not have a budget for a smart plug, they shut off hot water during guaranteed unused hours.
• Time of use electricity rate: if not already active, align main consumption (washing machine, boiler) with cheaper hours. This is especially useful if you have a cleaner running multiple laundry loads between checkouts.
• Clear house manual: including simple instructions on the air conditioner and heating, even just a couple of lines, reduces improper usage on its own. It is the zero cost measure with the highest effort to result ratio.

Only after addressing these points does it make sense to evaluate smart technology, which serves to automate what would otherwise require continuous manual oversight.

Before buying: check these 3 points, or risk wasting money

These are the most common reasons a smart thermostat ends up unused after a month:

1. System compatibility: many older boilers lack the common wire (C wire) required by smart thermostats, or operate with a single valve that is incompatible without minor electrical work. Before buying, check the boiler model or have a technician verify compatibility. It is a 30 to 50 euro cost that avoids purchasing an unusable device.
2. Centralized or building heating: if the property is in a building with centralized heating, you do not control the boiler. Smart valves only regulate the local valve on individual radiators, offering a more limited benefit compared to an independent system. They remain useful, but expected savings percentages must be adjusted downward.
3. Wifi reliability: a smart system relies on connection. With a cheap router or weak signal in some rooms, devices often remain stuck on the last received setting. This is a major issue especially for remote managers. It is worth checking Wifi coverage where you plan to install sensors before buying the full set.

How much smart devices cost and how much they truly save

The following data comes from industry studies (BTicino/EN 15232, A2A Energia) and current prices on the Italian market, with savings percentages that should be read as realistic ranges rather than absolute guarantees:

The typical return on investment for a smart thermostat with valves in an uninsulated building is around 18 or 19 months; in an insulated building it rises to about 22 months, but with a higher percentage saving over the long term. For a vacation home with frequent guest turnover, the actual return is often faster than these residential averages, precisely because guest lack of awareness generates more avoidable waste.

Beware of overly inflated numbers: some manufacturers advertise savings up to 37% or 73%, but these are marketing figures based on optimal cases. For a conservative and realistic estimate, it is better to target the range between 15% and 30%, consistent with independent studies.

The tax bonus that lowers real investment

Smart thermostats, thermostatic valves, and thermoregulation units fall under the so called domotics bonus within the Ecobonus and Renovation Bonus: a 50% deduction for primary residences and 36% for second homes and other properties (the bracket concerning most vacation rentals), recovered in 10 annual quotes on tax returns. It is not an immediate discount, as the full expense must be fronted.

There are specific technical requirements (system energy class, low thermal inertia valves, and in some cases ENEA notification), so it is best to confirm eligibility with your technician or accountant before purchasing. If you operate with a VAT registered business for short term rentals, the devices are often deductible as operating expenses, an alternative to the bonus worth evaluating with your accountant based on convenience.

3 level framework: how much to invest, how much you save, payback time

As a baseline, we use an average annual utility bill (gas + electricity) for a tourist use one bedroom apartment of around 1,500 euros per year. This benchmark applies to an average climate: in areas with long winters (mountains, northern Italy) the baseline bill is typically higher and euro savings proportionally larger; in mild climates, the opposite applies.

A final note on numbers: if you combine multiple levels (for example Base + Intermediate), total savings are not the sum of both percentages, because a portion of waste already eliminated by zero cost measures is no longer available to recover with the smart thermostat.

Example 1: One bedroom apartment, Intermediate level

Seaside apartment, actual annual bill of 1,400 euros, medium to high occupancy in summer. Investment: 120 euro smart thermostat, two 30 euro window sensors, one 25 euro smart plug for the boiler, total 205 euros. At 20% savings, annual savings are around 280 euros. Payback time: just under 9 months.

Example 2: Two bedroom apartment, Advanced level

Mountain apartment with 4 radiators, actual annual bill of 2,600 euros (extended winter use). Investment: 180 euro multizone thermostat + 320 euro set of 4 smart valves + 90 euro for 3 sensors + 150 euro professional installation, total 740 euros. At 28% savings, annual savings are around 728 euros. Payback time: around 12 months, within the first full winter season.

How to choose the right level

• If the annual bill is below 1,000 euros, the Advanced level almost certainly will not pay off in a reasonable timeframe: start with Base and consider Intermediate only if actual waste is high.
• If you manage multiple similar properties, test the Intermediate level on one unit for 2 or 3 months before replicating it across all of them.
• Upgrading to Advanced makes sense primarily for properties with multizone central heating, where waste from uncontrolled zones is structurally higher.

Technology alone is not enough without a clear procedure between owner, cohost, and maintenance worker:

• Before arrival: check that temperature, boiler, and split units are in the correct mode for the season.
• Message to guests: a simple line in the house manual or on WhatsApp, for example: "For your comfort, the air conditioner works best with windows closed. If you need to adjust the temperature, text us and we will assist you right away." Collaborative tone, never punitive.
• During stay: if an alert for an open window or abnormal consumption arrives, the cohost contacts the guest courteously.
• After checkout: reset all systems to standby or eco mode.

For cleaners and maintenance technicians, this protocol reduces unnecessary interventions: fewer calls for rooms that are too hot or cold, fewer boilers left on, and fewer vague issues to decipher.

Technical limits and transparency with the guest

A guest can disable the application on their phone, cover a sensor, or unplug a smart socket: the system reduces average waste, it does not eliminate it entirely, and should not be presented or used as a surveillance tool. Savings percentages already account for a portion of behavior that no device can fix.

Furthermore, sensors and consumption monitoring during the stay touch on transparency. It is worth stating in the listing or house rules that door and window opening sensors or energy monitoring are present: it is not specifically required by law for these devices, but it avoids disputes and maintains high guest trust.

Certain signs indicate it is better to involve a technician or maintenance worker rather than doing it yourself:

• Bills rising even with stable occupancy.
• Guests repeatedly reporting too hot or too cold temperatures.
• Boilers remaining active between stays despite settings.
• Repeated maintenance for systems stressed by continuous improper use.

An experienced maintenance technician verifies system compatibility, electrical safety, correct sensor placement, and Wifi signal quality, factors that determine whether a smart system works properly or gets abandoned after a month due to false alarms.

If you are looking for a qualified technician or an experienced maintenance worker to set up these systems in your vacation home, you can find the right professional for your area directly on Hostbudd, connecting directly without middlemen with the best local skills.