The assumptions behind the numbers

Where the numbers on chargego.pl come from

The numbers on this site (daily charges, solar output, contribution to certification, avoided emissions) are calculations based on public data and stated assumptions. Below, for each one: the assumptions, the formula, the result, the limitations and the source.

~29 charges per day in summer

The number of full charges of a typical e-bike battery you can get from a shelter with 10 charging points on a sunny summer day.

Assumptions
  • Bike battery: 500 Wh (2025–2026 e-bike market median: 400–625 Wh)
  • Depth of discharge: 80%, since most riders don't run a full cycle
  • Energy per charge: ~0.5 kWh (with a margin for losses)
  • Summer PV output: ~16–17 kWh per day from 3.48 kWp (June–August, central Poland, PVGIS data)
  • System efficiency: ~90% (inverter, MPPT, BMS, cabling)
Result: 16.5 kWh × 0.9 ÷ 0.5 kWh ≈ 29–31 full charges on a sunny summer day. Plus a buffer from the LFP battery (~6 kWh) for morning and evening sessions when there's less sun.
Limitation: this figure covers full charges from 0% to 100%. An e-bike is rarely at 0% when plugged in; a typical session tops up 30–60% of capacity, so the real number of sessions is often higher.

Energy cost in off-grid mode

The marginal cost of energy is zero: that is the cost of the next charging session on an installation already running. The total cost is not zero, because the solar and battery investment sits in the unit's price regardless of how many sessions take place.

What this means
  • In off-grid mode, the shelter produces all of its energy from solar.
  • The site operator (hotel, municipality, company) doesn't buy electricity from a utility for the shelter.
  • This doesn't affect grid connection agreements and doesn't raise electricity bills.
An important distinction
  • LOGISTERS Sp. z o.o. (operator of the ChargeGo service) is not an electricity retailer.
  • The site operator decides how to bill end users for charging sessions: paid, free or through a loyalty card.
  • In hybrid mode (230 V grid backup), the operator draws extra power from the grid only when solar and battery storage fall short.

Full billing terms are in the Terms of Service.

PV output ~3,400 kWh/year

Annual energy output of the 3.48 kWp solar roof on a shelter with 10 charging points.

Source

PVGIS data (Photovoltaic Geographical Information System, European Commission Joint Research Centre). Typical yield for central Poland: 950–1,000 kWh/kWp/year at optimal orientation (south-facing, 30–35°). For 3.48 kWp that works out to ~3,300–3,480 kWh/year.

Actual output depends on the shelter roof's orientation, tilt angle, shading and local weather. We calculate it individually for each site. PVGIS is available at re.jrc.ec.europa.eu/pvg_tools/en/.

Support for BREEAM / LEED / WELL / DGNB certification

Upper limits of the shelter's contribution to four major green building certification systems. We don't add them up into one combined score, because every project targets a specific system such as BREEAM Excellent or LEED Gold.

Upper contribution limits, per system
  • BREEAM In-Use v6 · Tra, Cyclist Facilities: typically up to 4 points (cycling infrastructure, comfort, security, support for low-emission vehicles). The criterion where the shelter covers the most requirements.
  • LEED v4.1 · LT, Bicycle Facilities: typically up to 2 points. The shelter supports the credit, and the requirements also cover access to a bicycle network and end-of-trip facilities (showers, changing rooms) for some building types.
  • WELL v2 · Movement: active mobility and occupant wellbeing strategies. How features map to points (V01, V04 and so on) depends on the project's WELL scorecard.
  • DGNB · Mobility Infrastructure: up to 5 points. The most categories for mobility and e-mobility.
Important: the building or project gets certified, not the shelter. The numbers above are upper contribution limits; an assessor or certification consultant confirms final point qualification for the specific project.
Calculator with assumptions: /wiata-rowerowa-breeam-leed.

CO₂ emission reduction

Estimated emissions avoided by using solar power instead of grid electricity.

Assumptions
  • Poland's grid emission factor (2024): ~610 g CO₂e/kWh (source: KOBiZE)
  • One e-bike charge = 0.5 kWh = ~0.3 kg CO₂e (if it came from the grid)
  • Per year (200 working days × ~15 charges on average): ~1,500 charges
  • Annual reduction: 1,500 × 0.3 kg ≈ ~0.45 t CO₂e per shelter
This is a conservative figure: it leaves out secondary effects such as riders choosing a bike over a car. With that kind of modal shift the reduction can be many times higher, which needs behavioural data from the specific location.

Funding "up to 85%"

The maximum funding level available across programmes for local governments and companies.

Programmes with an 85% funding cap
  • FEnIKS (European Funds for Infrastructure, Climate, Environment): up to 85% for local governments investing in low-emission infrastructure
  • KPO (National Recovery Plan): mobility and clean energy programmes for local governments
  • RPO (Regional Operational Programmes): funding levels vary by voivodeship
  • NFOŚiGW programmes dedicated to micromobility
The actual funding level depends on the specific call, the project's characteristics and the beneficiary's status. Check the current list of open calls at an EU funds information point. This page lists the programmes and their upper limits; we don't run grant consulting.

Updates and versioning

Methodology version: 2026.05. We update PVGIS and KOBiZE data, funding programmes, certification protocol requirements and e-bike market parameters every six months, or sooner if a key source changes. Publication dates of the underlying public sources: the PVGIS API is continuously updated, the KOBiZE report covers 2024 (published 2025), BREEAM In-Use v6 (updated 2023+).

Have a question about the methodology? Get in touch
Methodology: the assumptions behind our numbers | ChargeGo