Electric Vehicle Charging — Algarve
Installing a charging point is presented as a simple job, and for a small number of houses it is. For most it is the largest single electrical load ever added to the property, and whether it works well depends almost entirely on decisions taken before anything is mounted on the wall.
iHome designs and installs charging for private homes, developments and hospitality across the Algarve, as part of the electrical and energy design rather than bolted on afterwards.
A charger is not an appliance
A 7.4 kW charger draws roughly 32 A continuously, for hours at a time. That is more than the rest of a typical house combined, and sustained far longer than an oven, a hob or an air conditioner ever runs at full output. Domestic electrical installations are designed around diversity — the assumption that not everything runs at once. A car charger breaks that assumption nightly.
This is why the first question is never which charger. It is what the supply can carry, and what happens when the car and the house want power at the same moment.
Choosing the power rating
More is not automatically better, and over-specifying is the most common and most expensive mistake.
| Rating | Supply | Current | Range added per hour* |
|---|---|---|---|
| 3.7 kW | Single-phase | 16 A | ~20 km |
| 7.4 kW | Single-phase | 32 A | ~40 km |
| 11 kW | Three-phase | 16 A | ~60 km |
| 22 kW | Three-phase | 32 A | ~120 km |
* Approximate, for a vehicle consuming around 18–19 kWh per 100 km. Efficiency varies considerably between models and with temperature and driving style.
A car parked overnight for twelve hours on a 7.4 kW charger receives roughly 400 km of range — far beyond typical daily use. Higher power earns its cost in three situations: vehicles that turn around quickly during the day, properties with more than one electric car sharing a supply, and vehicles whose onboard charger can actually accept it. That last point is frequently missed — the vehicle, not the charge point, sets the ceiling. Many cars accept only 7.4 kW or 11 kW on AC regardless of what is installed, and a 22 kW charger will simply deliver less.
Almost all charging in Europe is Mode 3 under IEC 61851, using the Type 2 connector. Tethered units, with the cable permanently attached, are more convenient day to day. Socketed units accept any cable and cope better with mixed vehicles and shared use.
Dynamic load balancing: the feature that matters most
If only one thing on this page is taken away, it should be this.
Without load management, a charger draws its full rating whenever a car is plugged in, regardless of what else is running. The household then discovers the limit the hard way: the oven, the induction hob, the air conditioning and the car coincide, the contracted power is exceeded, and the main breaker trips — typically at dinner time, and typically in front of guests.
The usual remedy is to increase the contracted power, which means paying more every month, permanently, for capacity needed a few minutes a day.
Dynamic load balancing solves it properly. A meter or current transformer at the supply point measures total consumption continuously. The charger receives that reading and modulates its own draw to fit within the remaining headroom — reducing to 6 A while the kitchen is busy, returning to full rate once it is not. The car takes longer on those evenings and finishes overnight regardless. Nobody in the house notices anything, which is the point.
Where several charge points share one supply — a development, an apartment building, a hotel car park — the same principle distributes available capacity between them rather than requiring an infrastructure upgrade sized for every vehicle charging simultaneously, which never happens.
Charging from your own solar
Where the property generates electricity, the charger can absorb surplus that would otherwise be exported at a fraction of its value. The system compares generation against household consumption and directs the difference to the car.
Three modes are typical: surplus only, where the car charges purely from what the array produces beyond what the house is using; a hybrid mode with a guaranteed minimum rate topped up from the grid; and scheduled charging, where a departure time and target state of charge take priority over economics.
The honest limit. IEC 61851 sets a minimum charging current of 6 A — about 1.4 kW on single phase. Below that the vehicle cannot charge at all. On an overcast day, or with a modest array, surplus may never reach that threshold, and the system either draws some grid power to make up the difference or waits. Solar-surplus charging is genuinely valuable, and it is not the same as free motoring. Anyone who tells you otherwise is selling something.
This is also the clearest argument for designing generation, storage, monitoring and charging together rather than as separate purchases. The interaction is where the value is, and it cannot be retrofitted between systems that cannot see each other.
OCPP, and why it is worth insisting on
OCPP — the Open Charge Point Protocol — is the open standard by which a charge point talks to a management system. Versions 1.6J and 2.0.1 are in common use.
For a single home charger it matters less. For anything shared it matters a great deal, because it means:
- The installation is not locked to one manufacturer’s cloud service, which may change terms, add fees, or be discontinued
- Access control by RFID card or app, so charge points serve residents or guests and not passers-by
- Per-user metering and billing, which is what makes charging viable in developments, hotels and tourist accommodation
- Monitoring and remote diagnosis, so a fault is identified before someone reports it
We specify OCPP-capable hardware as standard.
What a correct installation involves
Beyond the charger itself:
- Supply assessment. Contracted power, phases, existing load, and whether the board can accommodate the circuit.
- Dedicated circuit. Cable sized for continuous load over the actual run length, with voltage drop calculated rather than assumed.
- Fault protection. IEC 61851 requires protection against DC residual current. That means either a Type B RCD or a Type A device combined with 6 mA DC detection integrated in the charge point — the latter being the usual and more economical route, provided the unit genuinely includes it.
- Earthing. Verified by measurement. Where the supply earthing arrangement does not permit an outdoor charge point directly, a dedicated earth electrode or an appropriate protection device is required.
- Location and ingress protection. Outdoor units rated for the environment — coastal Algarve means salt air and strong UV, not just rain. Cable route and parking position considered so the cable reaches without being walked on.
- Load management. Metering at the supply point, and communication between meter and charger.
- Integration. Where the property has KNX or Control4, charging status and control belong in the same interface as everything else.
Developments, hotels and rental properties
Shared installations raise questions a private house never does: how capacity is allocated between users, how consumption is attributed and billed, who may charge and when, and how the infrastructure grows as adoption increases without rebuilding it.
The economical approach is nearly always to install cable and capacity for the eventual number of points while fitting only those needed now, and to rely on load management rather than an oversized supply. Retrofitting infrastructure into a finished car park costs several times what it costs during construction.
For tourist accommodation, charging has become something guests filter for. It is worth treating as an amenity with proper access control rather than an open socket.
Working with iHome
We design charging as part of the electrical and energy system — supply, generation, storage and vehicle together — because that is where it either works elegantly or causes problems. We have been installing electrical systems in Algarve properties since 2006, and we are an official Control4 dealer and certified KNX partner, nationally awarded for our KNX work.
To discuss a charge point, an upgrade, or infrastructure for a development, call (+351) 289 090 900 or email geral@ihome.pt.