Understanding how residential solar panels and battery systems work - and why optimizing them is challenging
Solar panels convert sunlight into electricity through the photovoltaic effect. Here's the simple version:
Photons (light particles) strike silicon cells
The energy knocks electrons loose
The moving electrons create electrical current
An inverter converts it to usable AC electricity
The catch: Solar panels only generate power when the sun is shining. No sun = no power.
Your solar panels might generate the most power at noon, but you might need the most electricity at 7 PM when you're cooking dinner and the sun has set. This is the timing mismatch problem.
Power your devices right now
Save it in a battery for later
Send it to the grid and get credit
Without a battery, you can only do options 1 and 3. With a battery, you have full flexibility.
Home battery systems (like Tesla Powerwall, LG Chem, etc.) are basically giant rechargeable batteries:
How much energy they hold (typically 10-15 kWh)
How fast they charge/discharge (typically 5 kW)
Energy lost in storage (typically 85-95%)
Number of charge cycles (typically 5,000-10,000)
Think of it like: A water tank for electricity. Solar panels fill it up, your home drains it, and you choose when to fill vs drain.
Here's where it gets interesting. Every 15 minutes, your home energy system makes decisions:
Electricity costs different amounts at different times
Will tomorrow be sunny or cloudy?
When will your family actually use power?
Can't charge/discharge too fast, can't exceed capacity
Every time you store energy, you lose some
Let's break down the math:
Total possible schedules:
Over 10^10
(10 billion) combinations
This is a combinatorial optimization problem - finding the best combination from billions of possibilities.
Traditional computers solve this by:
These work well! But they struggle as problems get bigger (like optimizing a whole neighborhood).
Quantum computers approach it differently:
The big question: Do quantum advantages actually appear for real-world energy problems?
Why does this matter?
A: That's a good start, but time-of-use pricing adds complexity. Sometimes it's better to sell solar power at peak prices and charge your battery with cheap overnight grid power!
A: $8,000-15,000 installed. Better optimization helps pay back this investment faster.
A: Not yet - only about 10-15% of solar installations include storage. But that's growing fast!
A: Most do have basic automation, but they use simple rules. Sophisticated optimization could save significantly more.