Build MeshCore solar repeater
Build a permanent solar-powered MeshCore repeater for 24/7 autonomous mesh network coverage
Why build a solar repeater?
A solar-powered repeater on your roof or tall building can enormously strengthen the MeshCore network. It runs 24/7 without needing to swap batteries, and often reaches 5-10km+ in all directions.
This complete DIY guide teaches you step-by-step how to build a reliable solar repeater. From choosing parts to weatherproofing and mounting. Suitable for beginners with basic soldering experience.
Why solar power for repeaters?
24/7 autonomous operation
Solar energy + battery buffer = repeater runs continuously, day and night, without you needing to do anything.
No electricity costs
Completely free after initial investment. No cables indoors, no rising energy bills.
Place anywhere
On roof, shed, lamp post, tree – wherever you want. No outlet needed, complete freedom.
Blackout-proof
During power outage your repeater keeps running. Perfect for emergency backup communication.
Educational project
Learn about solar power, battery management, weatherproofing. Skills you can apply anywhere.
Community contribution
Help the mesh network grow. Your repeater helps dozens of other nodes extend range.
Required parts (approximately €150-250)
Complete bill of materials for solar repeater build:
Solar panel calculation
How big should your solar panel be? Simple calculation:
Measure power consumption: ESP32 optimized = ~40mA average. 40mA × 24h = 960mAh per day. nRF52 = ~15mA × 24h = 360mAh/day.
Calculate wattage: 960mAh/day ÷ 1000 × 5V = 4.8Wh per day. With 50% efficiency (clouds, angle) = 9.6Wh needed.
Netherlands sunlight: Average 3-4 "peak sun hours" per day (winter: 1-2h, summer: 5-6h). Take 3h for conservative estimate.
Panel size: 9.6Wh ÷ 3h = 3.2W minimum. Recommendation: 5-10W panel for sufficient margin and winter months.
Battery size: 3 days backup = 960mAh × 3 = 2880mAh. Minimum 3000-5000mAh (1-2x 18650).
Build steps (approximately 3-4 hours)
Step 1: Test all components
Connect everything on breadboard first. Test if solar panel charges, battery voltage correct, node boots. Fix bugs now, not after weatherproofing!
Step 2: Solder connections
Solar panel → Charge controller → Battery → Buck converter → ESP32. Use thick wire (20-22 AWG) for power. Test voltage at each point.
Step 3: Configure MeshCore
Disable GPS (unless tracking), disable WiFi/BLE, set TX power 17-20dBm, enable router mode. Flash firmware, test range. See power optimization guide.
Step 4: Weatherproofing
Mount everything in IP65 box. Use silicone sealant around cable glands. Test waterproofing (hose test). Ventilation holes with Gore-Tex tape for condensation.
Step 5: Antenna mounting
Mount antenna vertically above the box. Use L-bracket or pole mount. Check connector waterproof (heat shrink + tape). Test SWR/range.
Step 6: Solar panel direction
Netherlands: panel facing south, angle 35-40° for year-round optimal. No shadows (trees/chimney). Test voltage during sunny weather.
Step 7: Final assembly & mounting
Mount complete setup on roof/mast/building. As high as possible = better range. Test 24-48h monitoring: battery charge/discharge cycles, node stays online?
Monitoring & maintenance
Battery voltage telemetry
Enable battery telemetry in MeshCore. Monitor via app: voltage drops at night, rises during day. If voltage keeps dropping: panel too small or too much consumption.
Check every 2-3 months
Clean solar panel (dust/leaves), check connections, test battery voltage. Replace battery after 2-3 years (500-1000 cycles).
Winter vs summer
In winter: less sunlight, possibly node runs 1-2 days on battery. This is OK as long as it recharges. Summer: excess energy.
Frequently asked questions about solar repeaters
How much does it cost to build?
Approximately €150-250 total. Cheaper than Seeed SenseCAP (€300+) but DIY work required. If you already have parts: €100 is possible.
Does it work in winter in the Netherlands?
Yes, but less optimal. Winter: 1-2 peak sun hours vs summer: 5-6h. Solution: larger panel (10W+), larger battery (10,000mAh+), or optimize power consumption (nRF52 chipset).
Do I need to be an electrician to build this?
No, basic knowledge of soldering + multimeter use is enough. This is low voltage DC (5-12V), not dangerous. Follow schematics carefully, test everything before mounting.
Can I buy ready-made solution?
Yes: Seeed SenseCAP Indicator/M2 or RAK WisGate solar kits. More expensive (€300-500) but plug-and-play. DIY is cheaper and more educational.
How long does the battery last?
18650 Li-ion batteries: 500-1000 charge cycles = 2-3 years with daily cyclic use. LiFePO4 batteries: 2000+ cycles = 5-8 years but more expensive and heavier.
What if there's no sun for days?
That's why you have battery buffer. With 10,000mAh battery + optimized ESP32 (40mA) = 10 days backup. Netherlands rarely has >5 consecutive days without sun.
Build your own solar repeater, strengthen the network
A solar repeater is the ultimate contribution to the MeshCore network. 24/7 online, no maintenance costs, range of kilometers. Time to build!