OFF-GRID · HYBRID MICROGRID

Solar Hybrid Microgrid for Off-Grid Telecom Towers — Diesel becomes backup only

Off-grid 4G/5G base stations and microwave repeaters burn 8,000-15,000 L of diesel per site per year — fuel logistics, theft, downtime and Scope 1 emissions are the real OPEX. LEONICS designs Solar PV + LiFePO4 + Hybrid Inverter so the generator runs only when it has to. How far fuel use falls depends on the tower load, how the PV and battery are sized, and the site's irradiance — for a 3 kW tower sized as in the worked example on this page, around 60-80%.

60-80%
Diesel fuel cut
99.99%
Uptime target (N+1)
18-30 mo
Payback
-40 ~ +65°C
Operating temp

Design figures for a system sized to this use case. What a given site actually gets depends on its load shape, the PV and battery sizing and its tariff — the worked examples below show the inputs.

The Challenge

Telecom towers in off-grid and weak-grid areas run on diesel — expensive to fuel, hard to service at scale, and every hour of downtime breaches the operator's coverage SLA.

  • Diesel OPEX — Off-grid BTS burns diesel 24/7 — fuel plus logistics to remote sites dominate tower operating cost.
  • Downtime = SLA penalty — A genset failure means the tower goes down — dropping coverage and breaching the operator's uptime SLA.
  • Battery degradation — Lead-acid banks fade fast under tropical heat and deep daily cycling, forcing frequent costly replacement.
  • No eyes on remote sites — With 134 sites across 7 regions, a fault without remote monitoring is found only after coverage already drops.
  • Grid instability — On-grid towers still suffer brownouts and voltage swings that stress and shut down telecom equipment.
Solar-primary, battery-buffer, diesel-backup — the topology flipped

The tower used to run on diesel with solar helping. Reversing that order is what takes generator run-hours down, and the mast keeps an uninterrupted DC supply throughout.

Telecom tower solar hybrid architectureA 3–15 kWp array and a 48 V LiFePO4 battery connect to the DC side of a 5 or 6 kVA NODEX Power Node, which supplies the tower equipment with uninterrupted DC. The existing diesel generator is demoted to a backup that auto-starts only on low state of charge. An SCU and MBMS report status to the NOC over 4G LTE.Existing gensetdemoted to backup · auto-start on low SOCSolar Rooftop3 – 15 kWp per siteBatteryLiFePO4 48 VNODEX Power Node5 / 6 kVATower load (BTS)uninterrupted DC supplySCU + MBMSto the NOC over 4G LTEDCACDC 48 VSolar first, battery as the buffer, diesel only as a last resortDCAC

Schematic. Battery chemistry, PV size and genset hours depend on the site irradiance and load profile.

Interested in this solution?

LEONICS designs custom solutions with ROI/Payback estimates before installation.