PRO 15.84kW — EG4 FlexBoss21+ GridBoss, 28.6kWh LiFePO4
Real build cost
Complete kit — advertised price is the real price.
Solar
15840W
Storage
28.6kWh
Inverter
16000W
Cost / W
$1.25
Cost / Wh
$0.69
System voltage
48V
Battery chemistry
LiFePO4
What's included
86% completeAll required components for a working system are included. No additional purchases needed.
Evidence
Cohort-normalizedComplete as sold — every standard role ships in the box.
0th percentile for $1.25/W
33th percentile for $0.69/Wh
Component breakdown
6 included · 0 missingPrice history
Price History
▼ 8% BELOW AVGLast observed at retailer: Sep 20, 2026. Days between observations carry the most recent known price — not new data.
Where to buy
Affiliate links — checking price won't cost you anything
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