Break-even

Long-term ROI vs the no-solar scenario.

Payback progress

22.7%Recovered

Time elapsed

2.6 Years

Status

On Track

Initial CAPEX

$45500.00

2 entries in the system-costs ledger

Yield to Date

$10327.82

realized $10268.56 + banked $59.26

602 kWh in NEM bank @ $0.18/kWh

Outstanding

$35172.18

77.3% remaining until ROI realized

Maturity Date

MAR 2035

Approx. 8.8 years remaining at current burn rate

Cumulative savings projection

Compounds today's $333/mo burn at 3.0%/yr Duke escalation and −0.50%/yr panel degradation. Break-even point marked.

Net profit (15Y)

$36439.05

Avg. annual yield

10.5%

Utility offset (life-to-date)

98%

Environmental impact

Derived from 67,112 kWh of solar production over the solar era. EPA equivalency factors.

785

Trees planted equivalent

47.6 t

CO₂ emissions averted

27.4 t

Coal burned avoided

201k

Clean EV miles powered

Cost breakdown by category

install$35000.00 · 76.9%

powerwall$10500.00 · 23.1%

Methodology & caveats

Total invested sums every row in the system-costs ledger
Yield to date sums per-month value, decomposed into realized (est_without_solar − bill_amount) and banked ((nem_end − nem_start) × rate). Sunny months with surplus production show high banked value; inverter-outage months show negative banked value as the stack drew down. The two sum to total per-month savings.
Maturity date linearly extrapolates outstanding debt at the current $333/mo burn rate. This is optimistic in the early years (production accelerates as seasonal coverage matures) and pessimistic in the late years (no Duke-rate-growth tailwind modeled).
Cumulative-savings projection compounds today's $333/mo burn rate by (1 + 3.0%)(1 − 0.50%) per year — Duke retail-rate escalation tailwind minus panel-output degradation. Doesn't account for the federal tax credit already taken or year-end NEM true-up payments. Bumping rate growth higher (Duke is currently asking for >5% in their pending rate case) accelerates break-even by ~1.5 years; stiffer degradation pushes it out by similar.
Default Duke rate when nothing better is available: $0.18/kWh, with a $35.70/month minimum bill floor.

Methodology & caveats

Total invested sums every row in the system-costs ledger

Yield to date sums per-month value, decomposed into realized (est_without_solar − bill_amount) and banked ((nem_end − nem_start) × rate). Sunny months with surplus production show high banked value; inverter-outage months show negative banked value as the stack drew down. The two sum to total per-month savings.

Maturity date linearly extrapolates outstanding debt at the current $333/mo burn rate. This is optimistic in the early years (production accelerates as seasonal coverage matures) and pessimistic in the late years (no Duke-rate-growth tailwind modeled).

Cumulative-savings projection compounds today's $333/mo burn rate by (1 + 3.0%)(1 − 0.50%) per year — Duke retail-rate escalation tailwind minus panel-output degradation. Doesn't account for the federal tax credit already taken or year-end NEM true-up payments. Bumping rate growth higher (Duke is currently asking for >5% in their pending rate case) accelerates break-even by ~1.5 years; stiffer degradation pushes it out by similar.

Default Duke rate when nothing better is available: $0.18/kWh, with a $35.70/month minimum bill floor.