Gregory J. Hassler

Radio-Controlled Solar Boat Project: Helios 1

I have built a radio-controlled, solar-powered, catamaran-style boat. As a DIY project guy and solar nerd, and inspired by Lukas from the True North Yachts YouTube channel, I decided it would be a fun project to build an R/C solar boat from scratch. I call it the Helios 1.

Helios 1 is a deliberate homage to Lukas's 11-meter solar vessel, Helios 11, scaled down to about 1 meter. The hulls are built from foam-core Schedule 40 PVC pipe rather than fiberglass, with a zero-hull-penetration design. Power comes from a small solar array through a Victron MPPT charge controller into a 6 AH LFP battery pack, driving a pair of counter-rotating underwater thrusters controlled by a differential thrust mix on the transmitter.

The build documents everything from hull construction to the RC mixing setup that gives it tank-steering-style control. Below you'll find a video walkthrough, a complete parts list with cost breakdown, and the technical specs for anyone looking to build something similar.

YouTube video:

[Coming soon...]

Physical Diagram (simplified)

Front view Helios 1 front view, main components Front elevation of the Helios 1 RC solar catamaran, proportioned from actual dimensions: 25 inch beam, 5 inch pontoon diameter, 22.75 inch solar panel raised on two narrow 1.25 inch riser blocks at the pontoon mount points, 11.75 inch electronics box mounted at the same elevation with its taller top visible behind the solar panel. Shows the two pontoons at roughly 75 percent submerged, and larger round pod thrusters mounted fully outside each pontoon on an angled bracket. Waterline Electronics box Victron + battery Solar panel 50W Renogy panel Riser blocks 1.25 in standoff Pontoon hull PVC, both sides Thruster Inboard mount
Top view Helios 1 top view, main components Top-down plan view of the Helios 1 RC solar catamaran, bow at left, stern at right. Shows the two pontoons with rounded bow and stern end caps 38 inches tip to tip, the solar panel mounted just aft of the bow caps, the electronics enclosure just aft of the panel, and the pill shaped pod thrusters aligned with the hull axis, mounted forward of the stern end caps and roughly half hidden under the pontoon. Bow end cap Dome cap, both hulls Solar panel 20 in, aft of bow Electronics box 7.5 in long Thruster ~3 in diameter Stern end cap

Wiring Diagram (simplified)

Helios 1 full wiring diagram Complete wiring schematic for the Helios 1 RC solar catamaran. The battery is the main power source. Solar panel feeds Victron MPPT, which charges the battery through a charge fuse and switch. The battery feeds out through a load fuse and load switch, routed with right-angle turns, to a 3-way XT-60 splitter, which powers the port and starboard ESCs and a UBEC. The UBEC powers the receiver, which sends CH1 and CH2 signal lines to the ESCs and reads an EXT-V sense line from Victron's load output. Electronics enclosure Sealed, watertight CH1 CH2 EXT-V sense MC4 Fuse 5A SW Fuse 10A SW XT XT XT Solar panel Renogy 50W XT XT-60 connector MC4 MC4 solar connector Victron MPPT Charge controller LiFePO4 battery Main power, 12.8V 6Ah Splitter XT-60, 3-way UBEC 5V regulator Receiver ER3C-i RX ESC Port 45A waterproof ESC Stbd 45A waterproof Thruster Port ApisQueen U01 Thruster Stbd ApisQueen U01

Specifications

Helios 1: R/C Solar Catamaran Specifications
CategorySpecificationValue
Dimensions
HullLength overall (est.)38 in (97 cm)
HullBeam (max, design constraint)25 in (64 cm)
HullDraft (est.)3-3/8 in (8.5 cm)
HullFreeboard~3 in (8 cm)
Weight
HullsPontoon weight (each, measured)6.48 lb (2.94 kg)
HullsPontoon weight (pair)~13 lb (5.9 kg)
All-upTotal weight, ready to run (est.)31 lb (14 kg)
Construction
Hull material4 in Schedule 40 foam-core cellular PVC DWV pipeCharlotte 4400 / IPEX series
Hull sealingDome End capsSchedule 40 slip caps, solvent welded
Cross BarsAluminum L-channelRenogy Tilt Rail Kit
Propulsion
ThrustersApisQueenU01 pod thrusters, counter-rotating pair
ESCsApisQueen45A waterproof
Cruise speedEst., pending water testing~2.3 mph
Top speedEst., pending water testing~4 mph
Turn rateCalculated (at ~20 in thruster spacing, 45% throttle cap)~45°/sec
Power & Charging
Solar panelRenogy rigid mono, 12V50W
Charge controllerVictron SmartSolar MPPT 75/10Bluetooth monitoring
BatteryTalentcell LF4011, 4S LiFePO4~12.8V nominal, 6Ah
Low-voltage cutoffReturn-home alarm threshold11.9V
Max Power8 amps @ 12.8v nominal102 Watts (estimated)
Cruise Power2.7 amps @ 12.8v nominal35 Watts (estimated)
Run TimeFull sun, Cruise speed∞
Run TimeBattery only, Cruise speed1.5 hour
Radio & Control
TransmitterRadioMaster MT12EdgeTX 2.12.2
ReceiverER3C-iExpressLRS
SteeringDifferential thrust, tank mix3 selectable drive modes
Range (est.)ExpressLRS rated range, not yet field testedTBD
TelemetryMain Battery VoltageRxBt via EXT-V sense
Project
Build startBased on earliest project activityJuly 19, 2026
First launch (est.)Pending final assembly and water testTBD

BOM:

Grand Total: $1,051.34

Download Parts List

Build Photos


V2 Thoughts

Upgrades I'm considering for an updated version: