When Do Portable Solar Panels Work Best?

A Set Of Solar Panels Generating Electricity

Solar power frameworks are seen as a vital apparatus in the energy supply for the present and people in the future.

They are the most efficient and effective solar energy generator today. The increase in demand for portable solar panels has urged manufacturers to pump more efficient solar panels into the market.

As solar energy continues to increase, more people are looking to find portable solar panel products that suit their needs. You can read through all the specs and product information on the type of products available on the market.

However, here is the big question that I have seen asked in online forums; what time of the day do portable solar panels work best?

On a side note! If you’re in need of a reliable and high-performance portable solar panel, We strongly recommend the Jackery SolarSaga 100W  Portable Solar Panel  (Amazon Link).

With a high conversion efficiency and foldable design, this solar panel is easy to transport and set up, making it perfect for outdoor activities like camping, hiking, and RV trips.

The US solar cell technology used in this panel ensures that you get the most efficient and reliable solar charging possible.

There is also a 60W option that is more affordable (Amazon Link)

In general, a portable solar panel works best between 11 am to 1 pm when the sun is at its highest. Also, assuming your solar panel lays relatively flat on the roof or the ground. If your panels are slanted towards the east, then the best times would be between 8 am-10 am as the sun is just rising.

Check out our review on How fast can a portable solar panel charge?

Likewise, it will mostly depend on the geographic location where you intend to use the portable solar panel. Generally, peak sunshine hours are from 9 am to 4 pm, but this does vary depending on the different seasons of the year; and location. For example, colder regions have fewer sunshine hours per day.

Another crude way to judge sunshine hours is if you cannot look at the sun eye to eye, that is the best time to use your portable solar panel.

If your portable solar panel uses a mono or PERC MONO type cell, it will also produce some energy even when there are clouds. Monocrystalline solar cells perform slightly better than the polycrystalline cell in low sunlight conditions.For more on this topic, check out our post titled Which Solar Panel Is Best, Polycrystalline, Monocrystalline, or Thin Film?

Consider the ideal day for solar panels. The sun is sparkling free, blue sky. Yet, how is the temperature for such a day? In all honesty, it is cool, not warm.

Clear Blue Sky At Mt. Fuji, Japan

Like other hardware, solar panels work all the more efficiently in cool temperatures, permitting the solar panel to deliver more voltage, in this way greater power. As the temperature rises, the solar panel creates less voltage and turns out to be less efficient, producing less electricity.

Solar panels work by utilizing approaching photons to energize electrons in a semiconductor to a higher energy level. In any case, the hotter the solar panel, the more the number; of electrons in the energized state. As such, this diminishes the voltage that the solar panel can create and brings down its efficiency.

Seven Most Efficient Portable Panels For 2021

Individuals decide to purchase portable solar panels since they are an excellent eco-friendly product. Users can utilize these to charge cell phones, tablets, or PCs.

To follow underneath is a table indicating the most effective portable solar panels in 2021 with the goal that we can help you purchase the best item for you. Additionally included are specs for every item.

Name WeightDimensionPower OutputPrice
Renogy 100W 12 V Foldable Portable Solar Panel26.6lbs/12kg19.9 x 27.2 x 2.28 inches100W$219.99
Jackery SolarSaga 100W Portable Solar Panel11.65lbs/5.3kg26 x 22.5 x 2.5 inches100W$635.97
Goal Zero Boulder 100W Briefcase25.9lbs/11.7kg26.75 x 21.75 x 3.75 inches100W$394.40
Goal Zero Boulder 50W12.4lbs/5.6kg21.75 x 26.75 x 1.75 inches50W$149.95
Goal Zero Nomad 20W2.25lbs/1kg13 x 1 x 8.5 inches20W$149.95
ACOPOWER UV11007 GD 100W25.6lbs/11.6kg19.69 x 25.6 x 2.9 inches100W$215.55
HQST 100W 12 V Off-Grid Polycrystalline Solar Suitcase21.75lbs/9.86kg20 x 27.3 x 3.1 inches100W$68.99
Features Of Some Of The Best Portable Panels In The Market

It is a common myth that solar panels do not produce energy during rain and cloudy days. However, this is not the case. Solar panels can still generate power even if it is a cloudy day or if it is raining. Solar panels will work when the light is reflected or incompletely hindered by clouds.

Photovoltaic panels can utilize direct or indirect light to generate power. However, they are best in direct sunlight. The rain does help with keeping the panels working productively by washing ceaselessly any residue or earth.

Relationship Between Heat And Solar Panel

Sun Hovering Over A Solar Portable Solar Board

Numerous individuals would comprehend and prefer not to realize what-changes in heat can mean for solar panel performance. Portable-solar panels tested at 77°F and are rated to perform at peak efficiency somewhere in the range of 59°F and 95°F.

Nonetheless, portable solar panels may get as hot as 149°F throughout the late spring. The solar panel efficiency decreases when the surface temperature reaches around 149°F.

Portable solar panels are; produced using exceptionally sturdy materials intended to withstand extreme weather conditions from; freezing winter climate to summer heat.

The temperatures of portable solar panels depend on factors like; air temperature, geographic area, level of direct daylight, and roofing material.

Portable Solar Panel Efficiency

Perhaps the main things to search for in solar panel efficiency. Efficiency values refer to the energy change rate from solar energy into DC power. If that efficiency is higher, at that point, it implies that your solar panel will be more modest, will, in any case, deliver a similar power output.

Efficiency is quite possibly the most crucial resource and pointers; the higher effectiveness implies lower weight, less surface territory, and top-quality execution, as just top producers plan the best efficiencies.

Perhaps the main things to search for in solar panel efficiency. Efficiency values refer to the energy change rate from solar energy into DC power. If that efficiency is higher, at that point, it implies that your solar panel will be more modest, and will, in any case, deliver a similar power output.

Portable Solar Panel And Humidity

Water Drops On Portable Solar Panel

One of the things that can affect the efficiency of solar panels is humidity. If you live in the Pacific region, Papua New Guinea, as an example, this probably does not come as a surprise.

Humidity affects and slows solar panels efficiency in two ways; The amount of sunlight hitting the solar panel surface can be refracted and reflected due to the small water droplets accumulating on the surface.

The process reduces the amount of energy the solar panel can generate over time. Degrades a portable solar panel lifespan, as continuous exposure to humidity does disturb the maximum efficiency level solar panel can generate energy.

In such cases, the cadmium telluride portable-solar panel is much better than the crystalline silicon cells and thin-film types.

How Long Do portable Solar Panels Last?

As an overall solar industry general guideline, solar panels last around 25-30 years. In any case, this doesn’t imply that they quit creating power following 25 years – it simply means that energy creation has declined by what producers consider to be a large sum.

Solar panels can keep working for a long time, provided that they do not damage by wind, garbage, or some other outside components. All because solar panels do not have any moving parts – they once in a while break from the inside and are typically just harmed by outside powers such as low racking arrangement or harsh climate.


Portable solar panel producers give a scope of warrantees that promise you will have backing and inclusion in the impossible occasion of the issue, for example, hail or falling tree limbs.

Force yield guarantees ensure that panel usage will not fall under a predefined level over the term of the warranty (typically 25 years).

For example, a manufacturer may place a-warranty to ensure that the pinnacle power yield will not fall under 85 percent for a very long time. A few manufacturers will likewise incorporate additional warranty guarantees a higher yield level throughout a more limited timeframe.

Take, for example, an optional warranty that may ensure no under 90% of the introductory force yield for the initial ten years. Panels often come with a craftsmanship warranty. This warranty secures customers against damaged panel parts, by and large, for the initial five years of activity.

Inverters likewise come with warranties, as a rule for a very long time. Get familiar with solar board warranties and different pointers of value in the EnergySage Manual for Assessing Solar Board Quality.

Low Cost Of Maintenance

Cartoon Carrying Solar Panel: Maintenance Jobs

Portable solar panels require little maintenance. For best performance, cleaning the portable-panel once a month is recommended for optimum performance. Manufacturers can offer warranties for up to 5 years for portable solar panels. 

You can always contact them if you have issues with your product, and apart from the guarantee provided, there is no additional maintenance required, so all you need to do is keep an eye for regular maintenance.

High-Quality Solar Cells

There are three types of portable solar panels out in the market. These include polycrystalline, monocrystalline, and thin-film portable solar panels. All product ratings vary according to their respective specs.

However, on most occasions, the monocrystalline portable solar panel has a slightly higher efficiency rating. The reason has been monocrystalline panels are composed of single-crystal silicon. Because of this, electrons move more freely, thereby producing more power out from the solar-panel to the device.


As the name implies, portable solar panels are remarkably light and easy to carry around. You can pack them in your backpack or RV. They are light weighted and are great for camping and hiking or for activities that involve going off-grid.

Overcharge Protection

Many portable solar panels do come along with charge-controllers. The purpose of the charge controller is to monitor the charging time of a portable-solar board.

They act as a threshold, protecting the portable solar panels from being overcharged. Also, some charge controllers do have features that allow solar panels to charge more efficiently and faster.

In general charge, controllers work by limiting the rate of electric current transmission from batteries. The inclusion of charge controllers to portable solar panels makes them more efficient by monitoring the portable solar panels and avoiding damages and overcharging, which may seriously affect the battery’s overall performance.

To sum up, a portable solar panel works best between 11 am to 1 pm when the sun is at its highest. Also, assuming your solar panel lays relatively flat on the roof or the ground. If your panels are slanted towards the east, then the best times would be between 8 am-10 am as the sun is just rising.


I am a very well-experienced techie civil engineer who’s extensively interested in solar panel technology and even more captivated by the potential of solar panels in supporting individual residential units.

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