How do solar panels generate electricity
By Team Faseeh Lall
Solar panels look simple from the ground. Dark rectangles on a roof, making power without noise, smoke, or moving parts. Inside, the process is just as quiet, and it starts not with heat but with light. When sunlight hits a panel, it sets off a chain that ends as usable electricity in your home and, in Washington, DC, sometimes as SREC value as well. This guide follows that chain step by step, then covers the part most explainers skip: what owners must watch once the system is running, because production problems rarely announce themselves. That watching has a name, solar system monitoring, and it is the difference between a system that performs and a system that slowly falls behind.
The short answer: sunlight to socket in five steps
Sunlight hits the panel. Photons, the tiny packets of energy in sunlight, strike the solar cells.
The photovoltaic effect begins. Inside each cell, light energy knocks electrons loose from silicon atoms.
An electric field pushes those electrons in one direction. That ordered flow is direct current, or DC, electricity.
The inverter converts DC into alternating current, or AC, electricity, the form homes and the grid use.
AC electricity powers your home. Surplus electricity flows through your meter to the grid, and your meter records what goes out and what comes back.
That is the whole journey. The rest of this guide explains each stage properly, then explains what can interrupt it.
Inside a solar panel
A solar panel is a sandwich of layers built around solar cells. Most solar cells are made from silicon, a semiconductor material. Each cell has two silicon layers treated differently so that one side carries a positive charge and the other a negative charge. Where the two layers meet, an electric field forms. That field is the heart of the whole system.
When photons strike the cell, they give electrons enough energy to break free from their atoms. Left alone, those electrons would simply fall back. The electric field stops that. It pushes the freed electrons in a single direction, and that movement is electric current. Metal contacts on the front and back of the cell collect the current, and wiring carries it out of the panel. A single cell makes only a small amount of electricity, so cells are wired together into a panel, and panels are wired together into an array. The array is what powers a home or a commercial property.
Two facts surprise most new owners. First, panels use light, not heat. A bright cold day can be good for production, while extreme heat can reduce how efficiently cells convert light. Second, panels still produce on cloudy days, because clouds block only part of the light. Output is lower, but it does not stop. At night, with no light at all, production stops, and the home draws from the grid or from stored energy if a battery is present.
The inverter, the system's brain
Panels produce DC electricity, but homes run on AC electricity. The inverter is the device that converts one to the other. It also watches the system: voltage, current, production, and fault signals all pass through it. When something goes wrong, the inverter is usually the first place the problem shows up, as an error message, a warning light, or a fault code in monitoring data.
String inverters
A string inverter serves a whole row, or string, of panels at once. It is a simple and common design. Its weakness is shared fate: if one panel in the string is shaded, dirty, or faulty, it can drag down the whole string's output, because the inverter sees the string as one unit.
Microinverters
A microinverter sits behind a single panel and converts that panel's electricity on its own. If one panel has a problem, the rest keep performing at their own level. Microinverters also make it easier to see which individual panel is underperforming, because each panel reports separately. The tradeoff is more devices on the roof, one per panel, instead of one central unit.
Neither design is right for every system. Roof shape, shading, panel count, and budget all matter. What matters for owners is knowing which type you have, because it changes how a fault appears: a string problem affects a group, while a microinverter problem affects one panel.
Where the electricity goes
Once the inverter produces AC electricity, it flows to your home's electrical panel and powers whatever is running: lights, appliances, heating and cooling. This happens first, before anything goes to the grid. Only the surplus, the electricity your home does not use at that moment, flows outward through your meter to the grid.
Your meter is the record keeper. It tracks how much electricity your system sends out and how much your home draws back, for example at night or on very cloudy days. Under net metering rules, surplus production earns credit that offsets later grid use. The exact rules depend on your utility and jurisdiction, so the credit arrangement on your bill is worth reading carefully rather than assuming.
A battery, where one is installed, changes the timing rather than the physics. Surplus electricity charges the battery during the day, and the stored energy powers the home at night or during an outage, within the battery's capacity. Without a battery, the grid plays that role: it absorbs surplus by day and supplies power by night.
What the explainers never tell you: after installation
Here is where most guides stop, and where ownership actually begins. A solar system can keep producing while a problem quietly develops underneath that production. A panel can look intact, the inverter display can look normal, and output can still be falling because of a loose connection, a damaged cable, a shaded string, or a protection device that has already operated once. Production problems rarely announce themselves with a bang. They show up as patterns.
Watch for these patterns:
One string or section producing nothing while the rest of the array produces normally.
Repeated inverter tripping, or the same fault code appearing again and again.
A sudden production drop with no change in weather, shading, or soiling.
Gaps in monitoring data that line up with fault events.
A tripped breaker or blown fuse on the solar circuit, especially if it trips again after being reset.
None of these is a do it yourself diagnosis, and none of them is a reason to open live electrical equipment. Electrical work belongs to qualified personnel. The owner's job is to notice the pattern, record it with dates and fault codes where available, and arrange a professional inspection. That record is also what makes a warranty claim or a repair visit productive: it turns a vague feeling that something is off into evidence a technician can act on.
This is where SAMS's services fit. Production monitoring flags the problem. Inspections verify it on site. Maintenance and repair coordination gets qualified personnel to it, and records are kept alongside, so the system's history stays clear for warranties, for a future sale, and for the owner's own decisions. SAMS's existing posts on monitoring, inspection, and maintenance cover each step in depth, and this post deliberately does not repeat them.
The DC difference: production can mean SREC value
In Washington, DC, a solar system's production can be worth more than the electricity bill it reduces. Eligible solar electricity can earn Solar Renewable Energy Certificates, known as SRECs. Each certificate represents a defined amount of verified solar production, and those certificates can be sold through a broker or aggregator. In plain terms, your metered production becomes a second product alongside the electricity itself.
Earning SRECs is not automatic. A system must be certified, its production must be recorded and verified, and the certificates must be created and sold in the market. In DC, certification runs through the Public Service Commission, and production is tracked in the GATS system. That is why production records matter so much: missing or incomplete records can mean missing certificates, and missing certificates mean lost value. It is also why a production problem is a financial problem, not just a technical one. A system that underproduces does not only save less on bills. It may also generate fewer certificates.
SAMS's role here is brokerage: helping owners register, track, and sell their SRECs, either on the spot market or at an agreed rate, depending on what the owner chooses. No outcome is guaranteed, and no price is promised in this guide, because SREC prices move with the market. What can be promised is process: verified records, tracked certificates, and sales handled properly. SAMS's SREC posts explain registration, contracts, and broker choice in detail.
Homes vs commercial portfolios
The physics is the same for a home and a commercial property, but the stakes scale up. A home has one roof and one system to watch. A commercial portfolio has many roofs, many strings, and many inverters, and a single fault can hide inside a large total. Portfolio owners need the same three things, more rigorously: monitoring that shows performance per site and per string, inspections that verify what the data suggests, and records that tie production to certificates site by site. That is why commercial asset management is a discipline of its own, not just a bigger version of home ownership.
Key takeaways
Panels convert light, not heat, into DC electricity through the photovoltaic effect.
The inverter converts DC to AC, watches the system, and is where faults usually show up first.
Surplus electricity flows through your meter to the grid and earns credit under your utility's rules.
Production problems show up as patterns: a dead string, repeated trips, unexplained drops, or data gaps.
In DC, verified production can also earn SRECs, which is why production records protect income as well as output.
Electrical work is for qualified personnel. The owner's job is to notice, record, and arrange.
Frequently asked questions
1. How do solar panels generate electricity?
Sunlight strikes silicon solar cells and knocks electrons loose. An electric field inside each cell pushes those electrons in one direction, creating direct current. An inverter converts that current into alternating current for your home and the grid. That is the photovoltaic effect, first observed in 1839.
2. What does the inverter do?
It converts DC electricity from the panels into AC electricity for your home. It also monitors voltage, current, production, and faults. String inverters serve a whole row of panels at once, while microinverters serve one panel each, so a single panel problem does not drag down the rest.
3. Do solar panels work on cloudy days or at night?
On cloudy days, yes, at lower output, because clouds block only part of the light. At night, no, because there is no light to convert. At night the home draws from the grid, or from a battery where one is installed.
4. Why has my system's production dropped?
Common patterns include a shaded or faulty string, a tripped inverter, damaged wiring, or a monitoring gap hiding the real picture. Record the dates, the fault codes, and which part of the array is affected, then arrange a professional inspection. Do not open live electrical equipment yourself.
5. What is an SREC, and why does production matter for it in DC?
An SREC is a certificate representing a defined amount of verified solar production. In DC, eligible systems can earn SRECs through PSC certification and GATS tracking, and sell them through a broker or aggregator. Because certificates come from verified production, underproduction can mean fewer certificates, which is why monitoring and records matter.
Solar panels do the physics on their own. Keeping them performing, and keeping their value intact, is a different job, and it never ends at installation. Monitoring watches production. Inspections verify what the data suggests. Coordinated repairs fix what is found. Brokerage turns verified production into SREC value. Together, that ongoing work is called solar asset management, and it is what turns a rooftop array from a one time installation into an asset that keeps earning its keep