Utility Perspective: Rooftop Solar + Battery vs. Natural‑Gas Peaker (Austin, TX)
Solar is auto‑sized to match the peaker’s annual energy. Solar and battery are modeled as independent utility assets. Battery can charge from grid off‑peak or solar curtailment. Avoided energy value is built from wholesale + T&D + congestion and then peak‑weighted.
Inputs
Defaults match your 60 MW peaker @ 3% CF, conservative Austin rooftop yield, and a 2‑hr battery. Revenue stack is utility‑owned. Gas and peaker O&M escalate 2%/yr real; solar/battery O&M held flat real.
Auto‑computed from stack; editable if you want a manual override.
Outputs
Utility‑owned value stack included in IRR. Peaker LCOE levelized with gas & labor escalation. Solar and battery LCOE/IRR computed separately and combined.
Metric
Peaker
Solar + Battery
LCOE (combined, levelized)
—
—
IRR (combined)
—
—
Year‑1 total annual cost
—
—
Land required (acres)
—
—
Peaker details
Peaker annual energy
—
MWh/year
Initial peaker capex (incl. land)
—
Peaker land
—
acres · upfront $
Year‑1 fuel + var O&M
—
$/MWh fuel; annual $
Capacity‑factor sensitivity (Year‑1 LCOE)
—
Solar + Battery details
Solar capacity required
—
kWdc (Austin rooftop)
Solar‑only LCOE
—
levelized PV-only
Initial solar capex (incl. rooftop space)
—
Rooftop area needed
—
ft² · acres‑equivalent
Battery size
—
MW / MWh
Battery net annual value
—
value stack − battery O&M (Year‑1)
Initial battery capex (incl. land)
—
Solar + battery capex after ITC
—
Battery annual throughput
—
MWh/yr shifted (pre‑RTE)
Battery value stack (annual)
—
—
Solar + battery land & space
—
battery acres · rooftop acres‑eq · upfront $
Notes / scope (Version v0.9 – 2025‑11‑22):
- Utility perspective: value = all‑in avoided cost (wholesale + T&D/losses + congestion/reliability) then peak‑weighted; plus ISO ancillary revenues (if utility owns asset) and avoided capacity value. No retail bill savings.
- Solar and battery are treated as independent utility investments; combined IRR/LCOE sum their costs/benefits. Battery can charge from grid off‑peak or from solar curtailment via charge‑mode selector.
- Gas and peaker O&M escalate at user rates in real terms; solar/battery O&M held flat real (low‑labor assumption). Solar degrades annually.
- Rooftop PV is higher‑cost than utility‑scale; you can approximate utility‑scale by lowering $/Wdc and raising yield inputs.
- Gas‑plant adjacent land often appears unused but may be restricted by safety/security/substation buffer zones and future expansion needs.
- Land/space costs treated as upfront capex; rooftop area uses power‑density input.
The version above includes gas and labor escalators.