Large detached family home, Filothei
Kalavryton 14, 15237 Filothei, Athens, Greece
€1,450,000
Substantial detached Filothei residence on a quiet garden street. Original 1980s oil boiler, uninsulated envelope and a large south-west roof make it one of the strongest retrofit candidates in northern Athens.
- Living area
- 285 m²
- Rooms
- 8
- Built
- 1988
- Occupants modelled
- 4
- Heating
- Oil boiler
- Region
- Attica
Site & energy profile — Attica
Solar conditions
- South-west pitched tile roof, 25° tilt
- 130 m² usable roof area
- 1,550 kWh/kWp regional yield · 6% shading derate
- Modelled at 1,457 kWh/kWp → 31,617 kWh/yr from 21.7 kWp
Load drivers
- Oil-fired central heating across 285 m² and eight rooms
- Outdoor pool pump and filtration through the Athens summer
- Split-unit cooling on all three levels from June to September
- One EV charged overnight in the basement garage
Resilience context
Mainland Attica grid — stable supply, rare short outages.
Stable Attica supply; backup priority is comfort during short summer-peak outages, not islanded operation.
Indicative storage for this profile: 16 kWh.
Home Energy IQ summary
Home Energy IQ score
Kalavryton 14, Filothei, Athens
Attica · 1,457 kWh/kWp modelled yield
Energy demand
178 kWh/m²a
Running cost
€12,546/yr
CO₂ footprint
24.83 t/yr
Potential after retrofit
Indicative annual saving
€4,192
Highest-impact next step
Smart energy manager & hydronic balancing
≈ €540/yr saved · payback 3.3 yrs
Recommended Home Energy IQ system
Property size of 285 sqm exceeds the HOME 10 envelope.
Modelled retrofit plan
Modelled for this Attica property at 1,457 kWh/kWp, with a €45,000 indicative budget and a bill-savings objective. Adjust the assumptions in the simulator to model your own scenario.
Annual saving
€4,192
Net investment
€35,165
incl. €600 subsidies
Simple payback
8.4 yrs
CO₂ avoided
8.37 t/yr
Your recommended Home Energy IQ configuration
VILLA ENERGY 30
Why this fits your property
- A 285 m² property using about 17,870 kWh of electricity a year sits inside the VILLA ENERGY 30 band (20,000–45,000 kWh/year).
- Your roof in Attica supports roughly 21,855 kWh of production a year, which the 15 kW inverter and 30–32 kWh battery are sized to use rather than export.
- Pool circulation and EV charging push the evening load up, so storage is sized above the entry system.
Projected solar production
21,855 kWh/yr
15 kWp · 1,457 kWh/kWp in Attica
Self-powered
88%
Catalogue range 65–85%
Estimated backup
11.4 h
Essential comfort loads at ≈2.1 kW
Indicative investment
from €31,900
≈ €337/month over 10 years, excl. VAT
All figures are indicative model estimates for comparison, based on the details you entered. Production, self-powered share and backup duration depend on real weather, occupancy and tariffs. Nothing here is a quotation or a guaranteed performance figure.
Included in this configuration
- Solar PV
- 15 kWp
- Hybrid inverter
- 15 kW three-phase
- Battery
- 30–32 kWh LFP
- Backup
- Whole Home
- Whole-home automatic backup
- Smart Energy Gateway
- Dynamic zero export
- Home Energy IQ Advanced
- Solar forecasting
- Battery optimisation
Indicative installed price. Final pricing is subject to property survey, electrical infrastructure, grid connection, roof conditions and final engineering design.
Step 3 · Configure upgrades
Optional improvements
Your system works without any of these. They are shown because something in your inputs suggests they could be worth discussing at the assessment.
EV CHARGE
Charges the car on surplus solar instead of peak-tariff grid power — typically €300–€600 a year on the mileage assumed here.
You reported an electric vehicle.
Charge power and savings depend on your vehicle, tariff and daily driving pattern.
V2H READY
Prepares the electrical architecture so the vehicle could later support the house during an outage.
Only worth adding while the installation is being designed — retrofitting is more disruptive.
Actual vehicle-to-home operation depends on vehicle compatibility and applicable regulation.
SMART VILLA
Adds circuit-level metering and automatic load shifting, so the pool pump, heat pump and boiler run on solar rather than at night.
A pool pump is one of the largest shiftable loads on this property.
Circuit visibility requires CT clamps at the distribution board; without them, circuit values are estimated.
ENERGY CARE
Continuous monitoring, alerts and an annual performance review so underperformance is caught early rather than at year end.
Recommended for every installation; can be added or dropped later.
A recurring service subscription, separate from the installed system price.
Step 4 · Payment options
≈ €303.11/month
10% deposit (€3,190) · 10 years · 4.90% p.a. illustrative rate
Modelled energy saving
€349.33/month
Net +€46.22/month
Illustrative repayment estimate only — not a credit offer, quotation or approval. It assumes an indicative 4.90% annual rate, equal monthly instalments and the indicative system price before VAT and any subsidy. Actual terms depend on the lender, your circumstances and the final assessed price.
Step 5 · Confirm with an assessment
Confirm your Home Energy IQ plan
A site assessment validates roof and mounting, the electrical panel and connection, permitting requirements and the final price. Everything above stays an indicative model until an engineer has seen the property.
Your plan so far
- · Recommended system: VILLA ENERGY 30 (Premium Independence) — from €31,900 excl. VAT, indicative
- · Property profile: Attica · 15 kWp modelled at 1,457 kWh/kWp
- · Modelled outcomes: 21,855 kWh/yr solar · 88% self-powered · ≈11.4 h backup (Essential comfort loads)
- · Options to discuss: base configuration only
- · Financing interest: not reviewed yet
Prefer to read first? Detailed financing calculator · How assessments work
Today
178 kWh/m²a
€12,546/yr · 24,832 kg CO₂
After recommended plan
169 kWh/m²a
€8,354/yr · 16,460 kg CO₂
Projected class movement
Cumulative saving over 10 years (with 3% annual energy price inflation): €48,057
What your recommended system delivers
Every line below is delivered by VILLA ENERGY 30 or one of its optional Home Energy IQ modules — ranked by impact per euro against your goal and budget.
Smart energy manager & hydronic balancing
Cheapest measure per euro saved and the data layer for everything that follows.
Optional add-on: SMART VILLA module
- Net cost
- €1,800
- Saving/yr
- €540
- Payback
- 3.3 y
Rooftop solar PV
Generates power at roughly a third of grid price for 25+ years.
Delivered by your recommended Home Energy IQ system
- Net cost
- €31,465
- Saving/yr
- €4,646
- Payback
- 6.8 y
Smart EV charger (11 kW)
Charges on surplus solar instead of peak-tariff grid power.
Optional add-on: EV CHARGE module
- Net cost
- €1,900
- Saving/yr
- €74
- Payback
- 25.7 y
Catalogue options outside your budget
Home battery storage
Shifts midday solar into evening use and raises self-consumption to ~70%.
Delivered by your recommended Home Energy IQ system
- Net cost
- €14,920
- Saving/yr
- €806
- Payback
- 18.5 y
All figures shown are indicative estimates generated from standardised building models and average market prices. They are not a certified energy performance assessment, an engineering report, or financial advice. Actual savings, costs, subsidies and payback depend on an on-site assessment of your property.
All figures shown are indicative estimates generated from standardised building models and average market prices. They are not a certified energy performance assessment, an engineering report, or financial advice. Actual savings, costs, subsidies and payback depend on an on-site assessment of your property.