Introduction

An isoline, also known as a range spider, shows the area an EV can reach from a given point with the energy it has on board. Select a vehicle and an origin, and the API calculates the isolines that mark the travel distance limit, as shapes you can place on a map. The calculation uses the real road network as its reference: it finds the furthest points the vehicle can reach by road, and the outline connects those points. The result is a filled area, not a line that follows roads, so the stretches between roads, such as forests or fields, can fall inside it.

Optimize an isoline for your goal

The same request can produce different isolines depending on what you optimize for. These are the most common goals, and the options that shape each.

Range map

Show how far a vehicle can drive from a point, for example around a city, as an area on a map. Choose how many polygons you get, up to 20, from a simple picture of the vehicle’s reach to finer steps for a gradient. Trade precision for speed with quality, and include ferries with ferry_connections, which increase the calculation time and the number of polygons. See visualize vehicle range.

Reachability check

Answer “can I make it there without charging?” for a specific vehicle, which helps address range anxiety. Start from the actual battery level with state_of_charge, keep a reserve with final_state_of_charge, or use round_trip to only include points the vehicle can also drive back to the origin from.

Reachable stations

Filter charging stations to the ones a vehicle can actually reach from where it is. Combine it with final_state_of_charge so a station only counts when the vehicle arrives with charge to spare.

Realistic conditions

Account for what changes consumption: weather or season, the weight the vehicle carries, and heating and cooling with climate control. Without a battery level, the isoline uses the vehicle’s full usable battery capacity, and weather defaults to real-time data.

Thank you for your feedback.

Was this content helpful?