Overview
How this machine carries the load.
A new cell site is often ready to go on air before utility power reaches it, and until it does, a temporary diesel generator runs it around the clock. 123-STG-42S51 is the all-in-one Tri-Brid™ for that job: solar, lithium storage and a diesel generator built into one trailer, so a single tow puts a complete power plant on the site with no second unit to coordinate.
It is rated for 10 kW continuous — the inverter sets that limit — with surges to 24 kW for motor starts. The 4.6 kW array produces 19.8 kWh on an average day into a 19 kWh lithium iron phosphate bank, and below 0.82 kW the sun and the battery carry the site on their own.
When the load runs higher, the controller starts the 10.8 kW diesel, runs it at full output — carrying the load and recharging the bank together — and shuts it down again once the bank is charged. At a steady 5 kW that is about 9.7 engine hours a day where the 40 kW generator telecom sites use for temporary power would run all 24, and 10.89 gallons of diesel a day instead of 16.8. The 89-gallon tank lasts 7.76 days between refuels, against 7.92 for the 40 kW alone on its larger tank; at 3.33 kW it lasts 12.76 days. Both engines are read by the same fuel rule: their own published figures, held at the lowest one below it. At a remote site every refuel is a truck, a driver and a day on the road, so the days between refuels are what make this the cost-effective way to keep the site on air. The engine is certified to EPA Tier 4 Final.
Output is 120/240 V or 120/208 V at 50/60 Hz with a 5 ms transfer, rated for operation from -4 to 140 °F (-20 to 60 °C).
Features and benefits
- Solar, lithium and a 10.8 kW diesel in one trailer — One machine to transport, place and service.
- Ten 460 W panels, 4.6 kW — Light loads run silent and burn no fuel.
- 89-gallon tank, EPA Tier 4 Final engine — 7.8 days between refuels at 5 kW.
- 24 kW surge — Start-up spikes are covered without oversizing the engine.
Performance
Performance across the load range.
Zero to 10 kW, the rated maximum.
engine hours per daydiesel, US gallons per daythe array carries the whole dayrated continuous output
| Loadcontinuous, 24 h | Solar generationthe array, per day | Battery only | Daily drawload × 24 h | After solar | Days of autonomy | Generator | Engine runsa day × each | Charge setting | Days on a tank |
|---|---|---|---|---|---|---|---|---|---|
| 0.82 kWsolar break-even | 19.8 kWh | 11.25 h / 15.75 h | 19.8 kWh | covered | indefinite | 0 h/day | none | 173 A | — |
| 1.67 kW | 19.8 kWh | 5.56 h / 7.79 h | 40 kWh | 20.2 kWh | 0.46 days | 2.04 h/day | 1.8 × 1.2 h | 173 A | 37.4 days |
| 3.33 kW | 19.8 kWh | 2.78 h / 3.89 h | 80 kWh | 60.2 kWh | 0.15 days | 5.87 h/day | 4.3 × 1.4 h | 146 A | 12.8 days |
| 5 kW | 19.8 kWh | 1.85 h / 2.6 h | 120 kWh | 100.2 kWh | 0.09 days | 9.66 h/day | 5.5 × 1.8 h | 113 A | 7.8 days |
| 6.67 kW | 19.8 kWh | 1.39 h / 1.95 h | 160 kWh | 140.2 kWh | 0.07 days | 13.36 h/day | 5.4 × 2.5 h | 81 A | 5.6 days |
| 8.33 kW | 19.8 kWh | 1.11 h / 1.56 h | 200 kWh | 180.2 kWh | 0.05 days | 16.97 h/day | 4.1 × 4.2 h | 48 A | 4.4 days |
| 10 kW | 19.8 kWh | 0.93 h / 1.3 h | 240 kWh | 220.2 kWh | 0.04 days | 20.5 h/day | 1.6 × 12.8 h | 16 A | 3.7 days |
Every load here runs continuously, and the day is 24 hours — daily draw is the load × 24 h, so 2 kW is 48 kWh. A load that runs an 8-hour shift draws a third of the figure shown and lasts three times as long. Battery-only hours are given at both state-of-charge settings. Solar is a daily energy offset, not an instantaneous power match — over a day it balances, within a day it is not a guarantee of cover.
The engine starts at 30% state of charge (a 70% depth of discharge) and stops at 80%, putting 9.5 kWh back into the bank on each run while it carries the load. The engine runs a day follow from that at each load.
Case study
Against the 40 kW generator running alone.
At 5 kW around the clock, the 40 kW generator telecom sites use for temporary power would carry the site alone at 13% of its rating, 24 hours a day. 123-STG-42S51 runs its engine 9.7 hours a day — 60% fewer engine hours — and burns 35% less diesel: 10.9 US gallons a day against 16.8 US gallons, and 7.8 days between refuels against 7.9 days.
PDF The full engineering sheet with this case study, to print.
| Loadcontinuous, 24 h | 40 kW alonediesel a day, engine 24 h | Days on a tank40 kW alone | This systemengine hours a day | Diesel a daythis system | Days on a tankthis system | Engine hours saved | Diesel saved |
|---|---|---|---|---|---|---|---|
| 1.67 kW4% of the 40 kW | 16.8 gal | 7.9 days | 2.04 h | 2.3 gal | 37.4 days | 91% | 87% |
| 3.33 kW8% of the 40 kW | 16.8 gal | 7.9 days | 5.87 h | 6.6 gal | 12.8 days | 76% | 61% |
| 5 kW13% of the 40 kW | 16.8 gal | 7.9 days | 9.66 h | 10.9 gal | 7.8 days | 60% | 35% |
| 6.67 kW17% of the 40 kW | 16.8 gal | 7.9 days | 13.36 h | 15.1 gal | 5.6 days | 44% | 10% |
| 8.33 kW21% of the 40 kW | 16.8 gal | 7.9 days | 16.97 h | 19.1 gal | 4.4 days | 29% | 14% more |
| 10 kW25% of the 40 kW | 16.8 gal | 7.9 days | 20.5 h | 23.1 gal | 3.7 days | 15% | 38% more |
The 40 kW generator carries the load alone, 24 h a day with no sun and no battery, on its own 140 gallon tank (133 usable). Both engines are read by the same rule: their own published fuel figures, a straight line between them, and below the lowest published point that point’s burn — for the 40 kW, 25% of its rating. No lighter-load figure is invented for either engine. This system’s figures are the performance table above.
Size it for your site
Your load, on 123-STG-42S51.
Most sites swing between a low and a high. Enter both, and the hours a day spent at the high, and the figures follow your day rather than a flat worst case; add your diesel price for the fuel bill. The load is yours — nothing is assumed until you enter it, and nothing that names you is kept; the PDF button builds the engineering sheet from the figures you enter.
PDF The engineering sheet, with page two worked out for your load.
| Held flat at your high24 h at the high load | Your dayhigh and low, as entered |
|---|
Read from the performance table above: engine hours and fuel follow the day's energy, so your day is read at its average load; solar is the published daily figure; battery-only hours are the published bank at your high load. A load held for 24 hours is the worst case at that level. With no days entered it runs indefinitely; a week and a year are your day repeated, at the same sun.
Gallery
On site and on the road.
Applications