You want to know the difference between a system that WORKS and a pile of expensive equipment that doesn’t? NUMBERS! Real numbers from YOUR home. Not industry averages. Not a salesman’s pitch. YOUR electricity. YOUR site. YOUR sun.
The monopoly has been counting every kWh for YEARS. They know EXACTLY what you use and what they charge you for it. Time you learned the same.
This isn’t complicated. It takes a little time, a couple of cheap tools, and the willingness to actually look at what’s been draining your wallet every single month. Patriots do the homework. Let’s go!
YOUR Bill Is the Starting Point
Pull 12 months of electric bills. Your utility has this data online — they use it to charge you, you’re entitled to see it. Log in and get every month going back a year.
Monthly kWh consumption. Write down all 12 months. EVERY. SINGLE. ONE. You’ll see a pattern — higher in summer and winter, lower in the middle. That pattern shows you exactly when the monopoly has the most leverage over you. Solar hits them where it hurts most!
Your rate structure. Flat rate, time-of-use (TOU), or tiered pricing? This determines exactly what each kWh of YOUR solar production is worth. On a TOU plan, a kWh you avoid buying during peak hours — typically 4-9 PM — is worth MORE than one at 2 AM. A battery-paired system can arbitrage that spread every single day. See the rate calculator to see what the monopoly actually charges you, hour by hour. The number they bury in your bill!
Average daily usage. Monthly kWh divided by 30. That’s your baseline — the daily cost of renting electricity from a company with ZERO competition and NO accountability.
Measure YOUR Actual Loads
The bill tells you the TOTAL. Now find out WHERE the money is going. They won’t tell you. You have to find out yourself.
Kill-A-Watt meter (~$35). This device plugs between any appliance and the wall. Real-time watts, cumulative kWh over time. Plug your refrigerator into it for 24 hours. YOU’LL KNOW EXACTLY what it draws — not what the manufacturer claims, not a website’s guess. YOUR fridge. YOUR house. YOUR numbers!
Emporia Vue energy monitor (~$150). Clips onto your breaker panel. Logs usage per circuit, all day every day. More up front, but it gives you the COMPLETE picture — every circuit simultaneously, with historical data. If you want to see exactly where every dollar goes, this is the tool!
Nameplate vs. reality. Every appliance has a nameplate — the MAXIMUM it can ever draw. Most devices don’t run anywhere near that most of the time. A refrigerator rated at 800W might actually draw 65W all day. That 800W number is the compressor startup spike plus the defrost cycle running at the same moment. The nameplate is the ceiling, not the daily reality.
Here’s why BOTH numbers matter: typical draw tells you how much energy the device uses over time — that sizes your panels and batteries. The spike tells you the absolute maximum at any instant — that sizes your inverter. Confuse them and you’ll build the wrong system!
Devices aren’t constant. Your fridge hums along at 65W, then the compressor kicks and spikes to 200W, then twice a day the defrost cycle fires and it jumps to 800W for 20 minutes. A furnace fan runs at 250W but surges to 500+ on startup. A window AC draws 400W steady but needs 1,200W for a fraction of a second when the compressor engages. Brief spikes — but REAL ones. Your inverter has to handle every one of them.
Build YOUR Load Profile
List every device or circuit you want running on YOUR power — not the monopoly’s. For each one, record three numbers:
Continuous watts — what it draws while running normally. This is your Kill-A-Watt reading during steady operation.
Daily watt-hours — continuous watts times hours per day it runs. A 65W fridge running 24 hours uses 1,560 Wh (1.56 kWh) per day. A 250W furnace fan running 8 hours uses 2,000 Wh (2 kWh) per day.
Peak spike watts — the maximum instantaneous demand. Compressor starts, defrost cycles, motor surges. The numbers that size your inverter!
Realistic simultaneous load. Your peak demand isn’t everything spiking at the same moment — that almost never happens. It’s the realistic worst case of what actually runs at the same time. A teakettle and a microwave running at breakfast — about 2,800W together — that’s real. A washing machine and a teakettle simultaneously? Probably not. Think through your actual daily patterns and find the real worst case.
Add it all up. Three numbers come out:
- Average load (watts): typical continuous draw during the hours you’re actually using power
- Peak load (watts): realistic maximum when startup spikes overlap with other running loads
- Daily energy (kWh): total watt-hours across 24 hours for everything on YOUR list
Know YOUR Sun
You know what you need. Now find out what the sun can deliver to YOUR property!
Peak Sun Hours (PSH). The most important solar planning number — and the most widely misunderstood. PSH is NOT hours of daylight. It’s the total solar energy delivered to your location, expressed as equivalent hours of full-intensity sun. Five PSH might be five hours of blazing direct sun, or it might be ten hours of partly cloudy sky that adds up to the same total energy. The total is what matters, not the clock.
PVWatts (pvwatts.nrel.gov). Free tool from the National Renewable Energy Laboratory — that’s YOUR tax dollars at work! Enter YOUR address. Get monthly solar resource estimates specific to your exact location, accounting for latitude, local weather patterns, and typical cloud cover. Don’t guess when you can KNOW. Don’t estimate when government data is available for FREE.
General PSH guidance (verify YOUR specific location with PVWatts):
- Summer peak months: 5-6 PSH across most of the country. 73% of new solar went into TRUMP STATES. The media won’t report it. We just did!
- Shoulder seasons (spring/fall): 3-4 PSH
- Northern winter months: 1-2 PSH — the Sun Belt stays stronger all year
See the reference table below for an example monthly breakdown.
Walk YOUR property. Go outside on a clear sunny day. Find where you’d put panels. Watch the shadows — trees, neighboring houses, chimneys, dormers — at different times of day. A tree to the east might not matter if your panels face south. A tree blocking the southern sky is a genuine problem.
Shade isn’t always a dealbreaker, but it has to be in your plan. Shaded panels go on a separate string with their own MPPT input so one bad panel doesn’t drag down your whole array. Details in String Design.
Orientation. South-facing is ideal. East or west delivers roughly 80% of equivalent south-facing output — meaning a couple extra panels to match the same production. Small trade-off for a workable installation on YOUR roof.
Can I SHRINK This?
Before you start pricing equipment, run one more pass at your load profile. Every kWh you ELIMINATE is money you keep — equipment you NEVER have to buy!
This is “Insulate Before You Generate” made real. Ask what can come down:
- Always-on devices: that gaming PC drawing 150W around the clock — does it HAVE to be on solar, or can it stay on grid?
- Thermal loads: better attic insulation could cut AC runtime by an hour a day. That’s 400-600 Wh saved BEFORE you touch a single panel!
- 240V monsters: electric dryers and ovens drive battery sizing up sharply. Air-drying clothes or cooking with gas eliminates one of the biggest loads on your list entirely.
- Nice-to-have vs. need: separate them BEFORE you size the system. You can expand later.
Iterate. Revise the load profile, recalculate daily kWh, see how the system size changes. This loop costs NOTHING. The equipment costs plenty.
Napkin Math
Three inputs. Three formulas. First-pass system estimate. Let’s run the numbers!
Panel sizing:
Daily kWh target / Peak Sun Hours / 0.70 = total panel wattsThe 0.70 efficiency factor covers real-world losses — heat derating, wiring resistance, inverter conversion, dust, non-ideal angles. It’s conservative by design. Build in the margin.
Example: 10 kWh/day / 5 PSH / 0.70 = 2,857W. Call it 3 kW. That’s seven to eight 400W panels — made in AMERICA if you’re buying right!
Note: this is sized for summer production. Those same panels at 1.5 PSH in December produce less. That’s EXPECTED — design for the productive months. Use storage or selective grid backup to bridge winter shortfalls.
Battery sizing:
Overnight load (watts) x hours of coverage / 0.85 = minimum battery WhThe 0.85 accounts for depth-of-discharge limits and round-trip efficiency losses.
Example: 500W overnight load x 10 hours = 5,000 Wh. Divided by 0.85 = approximately 5,900 Wh. Call it 6 kWh to get through a summer night. Double it for a full day of autonomy with ZERO solar input.
Inverter sizing:
Peak simultaneous load x 1.25 = minimum inverter continuous ratingThe 1.25 multiplier keeps your inverter out of redline during normal operation. You want headroom. Running at 100% capacity is not how you make equipment last.
Example: 2,400W peak realistic load x 1.25 = 3,000W minimum continuous rating. Make sure the surge rating — typically 2-3x continuous — handles your largest motor-start loads.
These are ballpark numbers: “roughly a 3kW array, 6 kWh of battery, 3,000W inverter.” Enough to start researching REAL equipment and pricing REAL American-made components. The design pages refine these into actual specifications.
Ready to keep moving? Go to Panels and String Design. Run your full system scenario in the Energy Lab.
Reference: Common Device Wattages
Typical ranges from manufacturer specs and field data. Measure YOUR devices with a Kill-A-Watt. YOUR numbers are what matter!
| Device | Typical Draw | Spike / Peak | Typical Daily Usage |
|---|---|---|---|
| Refrigerator | 60-80W | 200-800W (compressor + defrost) | 1.5-2.0 kWh |
| Standing freezer | 80-100W | 200-500W (compressor) | 1.5-2.5 kWh |
| Furnace fan | 250-400W | 500-800W (startup) | 2-4 kWh (depends on run time) |
| Window AC (inverter) | 400-600W | 1,000-1,500W (compressor start) | 3-6 kWh (depends on heat/runtime) |
| Internet router + modem | 15-30W | minimal | 0.4-0.7 kWh |
| LED lights (whole house) | 100-300W | minimal | 1-2 kWh |
| Microwave | 1,000-1,200W | same (resistive load, no spike) | 0.1-0.3 kWh (short use) |
| Electric kettle | 1,200-1,500W | same (resistive) | 0.1-0.2 kWh (short use) |
| Clothes dryer | 4,000-5,500W (240V) | same | 2.5-4.0 kWh per load |
| Electric oven | 2,000-6,000W (240V) | same | varies widely |
| Washing machine | 300-500W | 500-800W (motor start) | 0.3-0.5 kWh per load |
| Laptop charging | 30-65W | minimal | 0.2-0.5 kWh |
| Desktop gaming PC | 150-400W | same | 3.6-9.6 kWh (if always on) |
| Phone charging | 5-20W | minimal | 0.05-0.1 kWh |
| TV (LED, 50-65”) | 50-100W | minimal | 0.3-0.8 kWh |
| CPAP machine | 30-60W | minimal | 0.2-0.5 kWh |
| Sump pump | 300-800W | 1,500-2,500W (startup) | varies (intermittent) |
| Well pump | 750-1,500W (240V) | 2,000-4,500W (startup) | varies |
| EV charger (Level 1) | 1,200-1,400W | minimal | 8-12 kWh (overnight) |
240V devices (dryer, oven, well pump, EV charger) require a 240V inverter. A 120V system CANNOT run these loads. Know this BEFORE you size your system!
Reference: Peak Sun Hours
Portland, OR monthly averages — illustrative example. Use PVWatts for YOUR address.
| Month | PSH (avg) | Notes |
|---|---|---|
| January | 1.2 | Shortest days, lowest sun angle, heavy clouds |
| February | 1.8 | Slightly better, still tough |
| March | 2.8 | Spring begins, noticeable improvement |
| April | 3.8 | Good production starts |
| May | 4.8 | Strong month |
| June | 5.5 | Peak production — longest days, highest sun |
| July | 5.8 | Best month — long days, clearest skies |
| August | 5.3 | Still excellent, days getting shorter |
| September | 4.0 | Solid shoulder month |
| October | 2.5 | Falling off |
| November | 1.5 | Winter begins |
| December | 1.0 | The bottom — plan accordingly |
Use PVWatts (pvwatts.nrel.gov) for YOUR location. That’s YOUR tax dollars paying for that data. USE IT!
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TAKE BACK YOUR POWER! Run your numbers, then get your FREE energy audit to see exactly what solar looks like for YOUR home. No salesman. No pressure. Just data — and the truth!
DATA SOURCED FROM: We’re using THEIR data against them. National Renewable Energy Laboratory (NREL) — PVWatts solar resource data and system performance modeling. Portland-area PSH values are approximate regional averages based on NREL satellite and weather data; individual results vary by location, orientation, and shading. Device wattage figures are representative ranges from manufacturer specifications and field measurements. Individual results vary — measure YOUR devices with YOUR tools.