Homeowners and others that employ solar panels often enquire: “Is it Okay to Walk on Solar Panels?” You hear “Yes” quite often, but is that really the case?
The answer can be complex. It depends on a number of factors, including the type of panels you may be walking on.
In the case of normal solar panels (roof arrays, for example), you should know that not all damage to solar panels may be visible. If you do walk on panels, you have to exercise adequate caution to ensure that you do not cause their efficiencies to drop significantly over time.
Let us investigate in more detail.
Is It Safe For People To Walk On Solar Panels?
Before getting started on a technical discussion about whether solar panels can withstand someone walking over them on a regular basis, let’s consider whether the person walking on a solar array can get harmed in any discernible way if s/he chooses to take that step.
Debunking a Myth: You Will Not Get Electrocuted By A Solar Panel
One reason people are sometimes warned not to walk on solar panels involves the possibility that they can get electrocuted.
Rest assured that this is nonsense. While solar modules do generate electricity within panels, the current is transported via appropriate and safe wiring to an inverter unit where the DC generated is transformed into AC to power household appliances.
You are not walking on a minefield with sparks of electricity – so whatever impacts arise, they will not be felt by you but by the surface and panels you are walking on.
Any Other Safety Issues When Walking Near Solar Panels?
There are more mundane safety issues, however. Typical solar arrays are made of glassy material that sits on surfaces such as rooftops, patios, decks of boats et al.
In some cases, the elevation and slant are not relevant – indeed, the array may be designed for many steps to traverse across the surface. But that is not always the case.
Take the case of solar panels sitting atop a residential home. Leaving aside the possibility of damage to the panels themselves, homeowners should be careful about walking on slanted roofs over panels made of glass.
Rain, snow, sleet, frost, and many other phenomena can make it extremely dangerous to be stepping on such a surface – a simple matter of a frost or slime buildup can cause tragic accidents. Additionally, roof arrays need to have a somewhat slippery texture by design so that dirt, debris, smoke, dust, pollen rinse off the roofing when it rains.
This in turn creates a dilemma – if you step on a roof, you should be wearing shoes that grip the surface. But if you choose footwear that will grip the surface by creating notches where you tread, the pointed shoes will have a greater propensity to harm the solar panel.
So is it ok to walk across solar panels, from the viewpoint of preserving the panels themselves?
Curious if you can overload a solar panel? Check this article out: Can You Overload A Solar Panel?
It Does Depend On The Type Of Panel
It is not uncommon to watch solar panel commercials reassuring homeowners about how robust they are. Oftentimes, the panels being touted pertain to those that are used in heavy walking areas. Some examples are:
- Solara’s Standard and Power M Series
- CMPower’s Semi-rigid Walk-On Marine Solar Panels with A+ Grade SunPower Cells
- Marlec Engineering’s Spectralite Walk-On Solar Panels
- Certain thin-film panels – more on that below
Some other types of panels, ostensibly designed to withstand weight, are mentioned in this regard. The jury is still out on the validity of the manufacturers’ claims in terms of how unbreakable or robust these panels are. Examples include:
- Tesla Solar Roofs are advertised as ones that people can walk on – however, not enough long-term data exists to determine whether those claims are true. Additionally, many of the reasons elucidated below will still apply in terms of how one should either avoid walking on them or be very careful doing so.
- Solar panels for sidewalks and roadways, such as the Solar Roadways system developed in the US, are mentioned as examples of panels designated for regular use that are able to withstand substantial weight in their natural course of use. While they are undoubtedly designed to withstand pressures, the viability of the systems overall is still not entirely clear – there have been stops and starts for many such programs, and the data is not always consistent.
Notwithstanding such specific designs, though, it’s safe to say that walking on standard solar panels (as described below) may be possible but is not recommended if you wish to avoid damage and expect the panels to produce electricity at peak or near-peak performances.
To explore this further, let’s examine how a typical solar array is built – with details of the units (cells, modules, and panels) that are key components of it.
The Components Of A Typical, Off-Grid Solar Array
The main components of an off-grid solar system are listed below:
- Solar Panels, containing (often photovoltaic) solar cells to absorb solar energy and ultimately produce Direct Current (DC).
- Batteries with Charge Controllers that store power to be used when little or no electricity is being generated by the panels.
- Inverter to transform the DC power to AC to run household appliances.
- Load Bearing Appliances, which are the end household units run on AC power.
- The Service Box with a breaker panel to safeguard in case of a short.
- A diesel, propane, or natural gas Generator may be added to an off-grid system as a back-up when no solar or battery power is available.
The key components of solar panels are the solar cells, which make up modules.
Solar panels come in all shapes and sizes, to learn the common size for residential read the following: What Size Are Residential Solar Panels? Let’s Find Out
Love the benefits of solar, but not a fan of the aesthetics? Check this article out: How To Hide Solar Panels On Your Roof
Many Solar Cells Make Up A Solar Panel
The basic principle of operation for a solar panel is as follows – photons (from sunlight) will knock electrons free from atoms, creating electric charge within a solar cell. Each panel is comprised of many solar cells.
Photovoltaic cells are one of the commonest types used in solar panels. Constructed with two slices of an efficient semiconducting material like silicon (usually crystalline silicon (c-Si)), these cells are designed to be able to convert as much sunlight into electricity as possible.
A discussion involving photovoltaic cells will serve to illustrate the delicacy of the system
Each Solar Cell Has Delicately Balanced Layers/Sections
Manufacturers of photovoltaic cells will coat the top layer with material (e.g., phosphorous) that will create a negative charge due to extra electrons, and the bottom layer with material (e.g., boron) that will create a positive charge. The “junction” between the two plates creates an electric field, which is essential to the functioning of the cell.
As each photon knocks electrons loose, the latter is pushed out of the junction by the field. A couple of other pieces, such as thin metal plates on the sides of the cells to catch the electrons being generated, and transferring them to wires, completes the function.
Many photovoltaic cells make up a “module”. Multiple modules make up a solar panel. Many panels fit into an array.
Other Designs Exist, But Each Type Of Solar Array Tends To Be Delicate
Some recent solar cell designs utilize ultra-thin (a hundredth of the width of a human hair) cells made from materials such as amorphous silicon (a-Si), Cadmium Telluride (CdTe), or Copper Indium Gallium Diselenide (CIGS).
A feature of ultra-thin cell designs is the cells’ ability to withstand pressure – for example, if trod on, the pressure is supposed to move quickly through the ultra-thin material and be transferred to the roof below. However, there is inadequate long-term data in terms of how efficacious these cells are in terms of withstanding pressure.
Other technologies, such as solar thermal and concentrated solar power (CSP) are also used.
Regardless of the technology used, it is generally true that most electricity-generating solar cells are delicately designed and balanced – which means that they can be damaged unless they are properly handled.
Bottom Line – Solar Cells And Modules Are Easy To Break
Many types of photovoltaic solar cells (contained within the panel) are delicately balanced, as described above. This in turn signifies that “invisible” damage may be caused by someone who walks, kneels down hard, or otherwise puts concentrated pressure on solar panels.
This is not to say that visible damage will not occur. There are certainly times when you can crack the surface, bend the frames or otherwise visibly alter the shape or angle of an array of solar cells. But for every instance of visible damage, there are probably multiple times when no outside damage is visible, but the cell or module has been “cracked” inside.
Just in case you’ve accidentally broken a panel or are considering setting up your first array and want to know if prices will come down, check this article out: Will Solar Panels Get Cheaper? Prices Are Trending Down
Damaging Solar Cells Through Breakage Will Reduce The Efficiency Of The Panels
If the damage is visible (e.g., bent frames or arrays, punched in, or deeply scarred successes), owners may take the necessary actions to get the cells required. However, if the cells are regularly walked or trod upon, without due care being exercised, a 10-30% efficiency loss can be quite common without much outside indication that such a deficiency is taking place due to this specific reason.
Given how each piece of a solar cell hangs together – from the upper and lower layers creating the electrical field to the side plates that “capture” the electrons being pushed out, to the wiring that connects to the rest of the system – it should be easy to understand how concentrated pressure at a point could create a breach.
The Effect Of Pressure Applied Through A “Point”
We discussed how the typical solar cell is a module, which is then connected into a solar panel, which in turn forms part of an array. Most solar panels are built with strong glass and aluminum covering so they can withstand inclement weather, such as heavy snow or torrential rain.
What this means, though, is that the panels are typically designed to withstand pressure across the entire set of panels…aka the solar array. If you apply concentrated pressure at any given point, the solar module will crack – imagine taking an ice pick and hammering against a specific point.
The impact of concentrated pressure could range from a “short” to the system that loses some of the power being generated, to the entire structure being compromised and no electricity is generated out of the system.
The Possibility Of Damage Makes It Harder To Maintain Solar Arrays
One thing to understand is that regardless of what you do, some attrition is inevitable due to the fact that any solar array has to remain exposed to natural elements in order to function. There are a great number of events that could cause rifts or fractures within an array – be it natural and gradual expansion or contraction, or the aftermath of a violent hailstorm.
While the performance may not dip precipitously without a specific, defined event (whether natural or human-influenced), there will be a gradual diminution in terms of energy output over time. This, in turn, may necessitate someone to walk on the panels to get repairs performed.
Repairs, therefore, are inevitable. It likely makes sense not to compound problems by walking on solar panels unnecessarily.
So, Should You Walk On A Solar Panel, Ever?
The answer to this question should go beyond “yes” or “no”. Almost inevitably, solar panels will need repairs – whether they are placed on more robust frames or less breakable surfaces, or they lie on your rooftop and over the years get compromised and less efficient due to simple natural forces relentlessly beating down upon them.
People, whether it’s you or service people, will likely need to walk on solar panels at some point in time. The trick is to do so skillfully, without causing further damage to the underlying solar cells, panels, or the array.
While it’s likely not a great idea for you to be walking on your roof, for some of the reasons mentioned previously, the guidelines below may provide indications of how you can do so without causing undue damage to the solar cells.
Remember that the key factors include how often you walk, your weight, and the amount of care you take in the process.
Wear Soft Soled Shoes – Clean Them Before Walking On Solar Panels
Hard-edged shoes or the presence of rock shards, pebbles, or other abrasive material stuck to the bottom of the shoe surface presents a major problem to solar cells. While the scuff marks may not be clearly visible to you, they will exist on the surface – pointing to damage to the solar cells below. Such scratches or scrapes can not only make the solar cells less efficient, but they can also go so far as to deactivate cells.
An even better idea, if it does not create a physical hazard, is to not wear shoes at all.
Understand That Any Abrasions Caused By Walking Will Only Get Worse With Time
In areas with significant temperature differences, there are bound to be normal expansions and contractions which the solar array structure must endure. If there are abrasions and scuff marks from boots when people walk over the solar panels, there will be multiple adverse effects over time.
Expansions and contractions are likely to broaden and deepen the initial scratches. Plus, debris from climatic conditions (e.g. dust, dirt, hail) will get into the grooves and expand them – causing more damage to the cells and modules below.
Leave It To The Professionals
Service professionals that work on Tesla Solar Roofs wear safety harnesses and know how best to move about in a manner that does not create additional problems to the solar panels. Unless you absolutely need to, call professionals to effect repairs. Do not get up on the roof yourself.
Summary: How To Protect Your Solar Panels If You Must Walk On Them
In general, you should not walk on your solar panels if you can avoid it. They are part of a delicate system that remains exposed to natural elements throughout the year. Once a chink appears in the armor, there will be steady degradation over time.
As mentioned above, though, there may be occasions when you or others may have to step on the tiles. Following the discussion above, here are some basic guidelines that should be followed:
- Wear either soft-soled shoes or no shoes if possible.
- Clean your shoes and/or feet prior to stepping on the solar array, to ensure that there are no pebbles, shards, or hard debris sticking to the soles – to avoid nicking the surface.
- If possible, adopt a crouching posture on four hands and legs and move gently with your weight spread around. This will ensure that there are no concentrated pressure points that could break the cells or modules below the surface.
- If crawling about on all fours is difficult given the elevation and slope, consider walking on tiptoes after having cleaned off the soles of your feet.
Final Thoughts
The discussion above should have made the concept clear. But just to reiterate, avoid walking on solar panels unless you have to. While the damage may not be immediately visible, damage to the underlying solar cells and modules will cause the efficiency of the solar energy system to diminish significantly. Over time, natural elements will exacerbate the effects.
While there are some panels that are designed to withstand constant and repeated pressure on them, most solar panels will contain cells that will be damaged if you apply concentrated pressure. There may be occasions when it’s necessary to walk on them, but take the proper precautions when and if such needs arise.