Current Energy Baseline · 13 Months (May 2025 – May 2026)
$4,738
Total Paid
13 months · $364/mo avg
26,383
kWh Used
~2,030/mo avg · 2 EVs
$0.180
Blended Rate
All-in avg · TOU ME-RESF
$780
Peak Month
Feb 2026 · 4,269 kWh · 24°F
44%
Super Off-Peak
EV + overnight · $0.148/kWh
⚠️ Usage pattern note: Peak consumption is in winter (Dec–Feb), not summer — likely electric heat and cold-weather EV charging. Solar produces least precisely when usage is highest. Payback depends heavily on net metering credit carryover from summer surplus months.
System Scenarios — Select to Explore
10 kW
Conservative
Annual production12,650 kWh
Grid offset52%
Gross cost$30,000
After 30% ITC$21,000
Yr 1 savings—
Payback—
15 kW
Recommended ★
Annual production18,975 kWh
Grid offset79%
Gross cost$45,000
After 30% ITC$31,500
Yr 1 savings—
Payback—
20 kW
Full Offset
Annual production25,300 kWh
Grid offset96%
Gross cost$60,000
After 30% ITC$42,000
Yr 1 savings—
Payback—
Monthly Production vs. Consumption
15 kW system · York County, PA estimate vs. actual usage
Production via NREL PVWatts, York County PA (~39.9°N, south-facing, 20° tilt). Summer generates a large surplus banked as net metering credits. Winter shows a deficit partially offset by those credits.
Monthly Bill — With vs. Without Solar
15 kW system · after net metering credits
25-Year Cumulative Net Savings
3% annual rate escalation · 0.5%/yr panel degradation · net of system cost
Month-by-Month Solar Impact
15 kW system · net metering with annual true-up
| Month | Usage (kWh) | Solar Est. | Net from Grid |
Actual Bill | Est. Bill w/ Solar | Monthly Δ |
Est. Bill w/ Solar = owed after net metering credit that month. Annual true-up may further reduce winter bills using summer surplus credits. Values use blended avg rate; actual varies by TOU tier.
TOU Rate Interaction — Why Timing Matters
Solar Production by TOU Window (Summer Weekday)
Approximate daily production distribution across rate tiers
On-peak advantage: Afternoon solar (2–5pm M–F) offsets charges at $0.289/kWh all-in — the most expensive tier. A slightly west-of-south array maximizes this benefit.
Rate Schedule — ME-RESF TOU
Effective Dec 1, 2025
| Tier | Gen | All-In | Hours | Solar |
|---|
| On-Peak | $0.2212 | $0.289 | 2–9pm M–F | ~35% summer afternoon |
| Off-Peak | $0.1089 | $0.176 | 6am–2pm + 9–11pm | ~65% of daily |
| Super Off-Peak | $0.0806 | $0.148 | 11pm–6am | None (nighttime) |
44% of current usage is super off-peak (EV charging + overnight loads). Solar doesn't offset these hours directly — a battery would shift daytime solar to nighttime use. Without storage, those SOP kWh still come from the grid at the cheap rate, which is fine.
Financial Analysis
Cost & Incentives
15 kW system
| Gross installed cost | $45,000 |
| Federal ITC (30%) | −$13,500 |
| Net out-of-pocket | $31,500 |
ITC is a dollar-for-dollar federal tax credit claimed in the year the system is placed in service. PA has no additional state income tax credit for solar.
Annual Savings
Year 1 estimates
| Solar production (kWh) | 18,975 |
| Grid offset | 79% |
| Annual bill reduction | $3,416 |
| Remaining bill est. | ~$1,322 |
| PA SREC income (est.) | +$380/yr |
PA SREC ~$20/MWh market rate. Volatile; treat as upside, not core savings.
Payback & Lifetime Value
Conservative (no SREC) · 3% rate escalation
| Simple payback | 9.2 yrs |
| Break-even w/ escalation | ~8.1 yrs |
| 25-yr gross savings | — |
| 25-yr net savings | — |
Battery Storage Consideration
Should Stille Hof Add Battery Storage?
Based on current TOU rate structure and usage pattern
Arguments FOR (e.g. Tesla Powerwall 3 · ~$15K installed)
- Store summer surplus for same-day evening use (2–9pm on-peak offset)
- Backup power for 1902 stone house — grid outage resilience
- Additional 30% ITC applies to battery installed with solar
- 2026 Model 3 supports V2H — EV as mobile storage
Arguments AGAINST (for now)
- SOP rate ($0.148/kWh) is cheap — overnight grid power is reasonable
- PA net metering provides retail credit — no urgency to self-consume
- EVs are ~150 kWh of mobile storage already
- Battery adds 3–4 yrs to payback; prices still falling
Bottom line: Start solar-only. Add battery in 3–5 years when installed costs drop further or if PA net metering policy changes.
Methodology & Assumptions
Solar production: NREL PVWatts for York County PA (39.9°N), south-facing, 20° tilt, 14% system losses. Monthly kWh/kWp: Jan 62 · Feb 80 · Mar 105 · Apr 125 · May 140 · Jun 145 · Jul 148 · Aug 135 · Sep 118 · Oct 95 · Nov 62 · Dec 50. Annual ~1,265 kWh/kWp.
System cost: $3.00/watt installed (2025 PA residential avg per NREL/EnergySage). Competitive bids range $2.50–$3.50/W.
Savings: Actual 13-month billing data from elec.dx1.dev. Uses blended avg rate ($4,738 ÷ 26,383 kWh = $0.1796/kWh). Actual savings may be 10–15% higher due to on-peak afternoon solar at $0.289/kWh.
25-year projection: 3% annual rate escalation (EIA 30-yr PA avg), 0.5%/yr panel degradation, no SREC income. ITC claimed year 1.
Property note: 1902 stone house. Roof structure, age, and orientation must be assessed by a licensed installer. Historic character may affect panel placement options.