Off-grid solar in Pennsylvania

Sun data: NASA POWERSized for December#36 of 51 for winter sun

The short version

In Pennsylvania's darkest month, December, panels tilted toward the sun get about 2.5 peak sun hours a day, from 1.7 to 2.8 depending on where you are. Sized for that, a typical off-grid home needs about 17 panels and 4 batteries; a cabin, 4 panels and 1 battery. Flat panels, like on a van roof, get 38% less that month.

Answer a few taps in a guide and every page like this shows the numbers for your own setup. Start

Every setup, sized for Pennsylvania

Each guide's usual answers, with Pennsylvania's December sun. Tap one to change the answers to yours.

Panels, batteries and cost for each kind of setup in Pennsylvania
SetupPanelsBatteriesAbout
Off-grid home 17 × 410 W 4 $10,000 – $12,000
Backup for my house 4 × 410 W 2 $9,000 – $11,500
Tiny house 7 × 410 W 2 $6,000 – $7,500
Cabin or shed 4 × 410 W 1 $4,000 – $5,000
RV, bus or skoolie 8 × 410 W 2 $6,000 – $7,500
Van 4 × 200 W 3 $6,000 – $7,500
Just emergencies or camping 4 × 200 W Power station $3,500 – $4,500

Van and RV numbers use flat-roof sun (1.6 h) and are capped by roof space, so they lean on driving and a generator in December. Costs are the gear only.

Sun in Pennsylvania, month by month

Tilted at latitude Flat. December gets 47% of the sun of the brightest month (5.3 h). Size for December and the rest of the year has spare.

Across Pennsylvania

Darkest-month sun differs by place. The 46 ZIP areas range from 1.7 hours in the 161xx ZIP area to 2.8 in the 189xx ZIP area. That's 66% more panel output for the same panels.

Winter sun in Pennsylvania and the nearest states
StateDarkest month, tiltedFlat
Pennsylvania2.51.6
Maryland2.91.8
District of Columbia3.22.0
Delaware3.01.8

Common questions

How many solar panels do I need to live off grid in Pennsylvania?

Sized for Pennsylvania's darkest month (December, about 2.5 peak sun hours on tilted panels), a typical off-grid home needs about 17 panels (410 W each) and 4 server-rack batteries; a cabin about 4 panels and 1 battery. Your own loads change this; the guides size it for you.

How many peak sun hours does Pennsylvania get in winter?

About 2.5 a day in December on panels tilted at latitude, and 1.6 on flat panels (NASA POWER, at the state's center of population), ranging from 1.7 in the 161xx ZIP area to 2.8 in the 189xx ZIP area.

Does off-grid solar work in Pennsylvania in winter?

Yes, if it's sized for December: that month gets about 47% of the sun of the brightest month, so a system sized for December has plenty the rest of the year.

Data: NASA Langley Research Center POWER Project, long-term monthly averages at Pennsylvania's 2020 Census center of population and at each 3-digit ZIP area. Method and downloads.