A Solar Pathfinder

The Solar Pathfinder is a standard shade analysis tool. You can use it to find out exactly where the shadows will be at particular times of the day or year. The data is in graphical form, so you can make sense of it at one glance.

Another popular tool is the Solmetric Suneye. This instrument is rather user friendly, but is much more expensive than the Solar Pathfinder. This will set you back by at least $1,500…yet there is a cheaper option.

Why Do We Need To Use A Solar Pathfinder?

A proper instrument like a Solar Pathfinder can save you lots of time and guesswork. Moreover it is reasonably easy to use and is affordable.

If we do not have any instrument to predict shadow positions, we’ll have to sit up from dawn to dusk to observe how they move. This is a waste of time! Moreover, these positions shift (slightly) through different seasons because of how the earth rotates around the sun.

But why do we care so much about the extent of shading? You may not realize this, but the effect of shading is devastating to solar energy production. Even if your solar panel is slightly covered under a shadow, the power output can drop drastically.

Consider this…if you shade only one solar cell out of the entire solar panel, your energy production is likely to drop by a third. If you shade a row of photovoltaic cells, your electricity output reduces by about 90%. This means your solar panels have virtually stopped working!

Therefore when installing your solar panels, shading is your first and most important concern.

But is it worthwhile to use a solar pathfinder? Perhaps we should ask ourselves if we could determine shadow positions without the use of a scientific instrument… In fact, the additional electricity you’ll be able to generate quickly covers the cost of the Solar Pathfinder. This is especially true for larger systems.

After all, you’ve invested money and effort on your solar cells, batteries and inverters… Are you going to sacrifice a potentially significant part of its energy output just to save a few bucks? I hope not!

In case you are thinking of installing solar panels without a Solar Pathfinder, drop the idea as soon as possible. Because guesswork will eventually cost you dearly! You may be concerned about the cost…or you may be worried about the complexity of the instrument. The fact is this instrument only costs $249 and you’ll probably take only 15 minutes to learn how to use it.

Whatever it is, if you’re without a Solar Pathfinder, I’m confident of this — you cannot even begin your installation… Without this instrument, you’ll be lost!

To use a Solar Pathfinder, you simply have to bring it to the spot you feel is most suitable for installation. Then you’ll need to level the instrument and point it to the right direction with the help of an in-built compass. The plastic dome will show you a paranomic view of the entire area together with the regions affected by shading over different times of the day or year.

To record your readings, you can use a wax pencil (or grease pen) to outline the shadow or simply use your digital camera to take a snap shot. (I prefer the second approach – it’s instantaneous!)

The effects of shading are exceedingly damaging to solar energy production. Therefore you need to eliminate the guesswork — which can end up costing you a lot — and adopt a scientific approach to install your solar panels. Among all known techniques, the easiest and cheapest way is to use a Solar Pathfinder.

Continue Reading:

1. Solar Panel Installation
2. Do-It-Yourself Solar Panels – Electricity Conversion From Sunlight
3. Used Solar Panels – How To Use Them To Build Cheap DIY Solar Panels

Currently there are solar panels that boast 30 percent efficiency. These are specially doped triple junction cells that began its development as dual junction cells. However these phenomenons are largely confined within the laboratory and engineers are still unable to produce such solar panels in large quantities without charging consumers an arm and a leg for it. More work remains to be done before common retailers stock up solar panels endowed with this technology.

In practical there is nothing much we as consumers can do about technology. Yet the little we do to ensure our solar panels achieve its maximum potential really goes a long way — especially since solar panels are designed to last us for a few decades.

The most important thing we can ensure is to install our solar panels in the right orientation and tilt angle. The optimal position helps photovoltaic panels receive the most sunshine throughout the day and across different seasons of the year. This helps reduce the payback period. If you are living in the northern hemisphere (like most of us do), then you’ll need to orientate your solar panels toward true south (as opposed to magnetic south). You’ll also need to tilt them according to the latitude of your installation site. The correct installation position will allow your solar panels to be exposed to direct, unobstructed sunshine from 9am to 3pm everyday.

Many homeowners underestimate the adverse effect that shading has on their solar panels. Even if only one solar cell is shaded, its entire solar generator’s power output can be dramatically reduced. The individual solar cell that is now shaded acts as a resister that drains the electricity generated by its neighbors. As resistance increases, power reduces.

Another seemingly minor event that reduces solar panel efficiency is the accumulation of dust on the glass surface. This dissipates sunlight that would otherwise reach photovoltaic cells for power generation. Since dust and dirt will inevitably collect, the only solution is to wash the glass surface regularly. If you’re living in a relatively dust-free environment, this should be an infrequent activity.

Temperature also affects solar panel efficiency. The higher the temperature, the further its efficiency drops. Unfortunately more heat is collected as solar panels experience more sunshine. Thus efficiency tends to taper as sunlight intensity increases. Therefore we have to ensure that our solar panels are installed sufficiently far away from roof shingles. The gap in between the roof and solar panels also allow air movement to bring away additional heat that may otherwise be trapped there.

Continue Reading:

1. Solar Panel Installation
2. Installing Solar Water Heaters
3. How To Clean Solar Panels — That Once-In-A-While Maintenance

Solar Panel Installation

Solar panel installation may be a daunting task for most people — it requires you to know where and how to site your solar panels. Moreover installation on roofs exposes you to the danger of falling. You are also at risk of electrocution while wiring your inverters.

But we do not have to be discouraged. Knowing what to do can help us tremendously and keep us away from danger. Some important installation know-how can make your job much safer and easier. Here are some points to consider before you install your solar panel…

In the northern hemisphere, we’d like our solar panels to tilt towards to south so that it can receive the most sunlight throughout the year. If we have a south-facing roof, all we need to do is line the solar panels along the surface of the roof. Otherwise we’ll need additional brackets to tilt the photovoltaic panels toward the south.

The roof is usually the best place to site your solar panels, but there are exceptions. Therefore you have to do a thorough survey to know where is the best place to locate your panels.

During the survey, you’ll have to take into consideration shading from plants and nearby structures. Shading has an adverse effect on solar energy production. The amount of electricity generated by photovoltaic cells reduces by a significant percentage with slight shading.

Through different seasons of the year, the position of the sun changes. So you’ll have to take this into consideration. An easy way to find the location that receives the most sunlight throughout the year is to use a Solar Pathfinder. This instrument shows you at a glance where shadows will be at different times of the day and different seasons of the year.

If the ideal location is on your rooftop, you’ll have to find out the maximum loading your roof can withstand. If the solar panels are too heavy, you will need to provide additional reinforcement to the roof structure before installation.

After the location is finalized, actual work can begin. You’ll have to get the correct solar panel mount to fix them at the ideal place — there are pole mounts, roof-ground mounts and flush mounts.

When installing on roofs, we frequently use flush mounts. This is the cheapest and easiest way to mount small solar panels. These are metal brackets that support both ends of a solar panel. It elevates the solar panels a few inches away from the roof to form a gap in between. This allows air to flow through, cooling the solar panels. It is vital to moderate the solar panel temperature so as to maintain the efficiency of photovoltaic cells.

Roof-ground mounts are grid-like structures that are used primarily for large solar panels. They can be installed on the ground or on roofs. A pole mount is used mainly for supporting a small, single solar panel.

After the solar panels are fixed, you’ll have to run and connect the electrical cables. The actual connections depend on whether you want a grid-tied or off-grid system.

With proper solar panel installation, each panel will be able to withstand strong winds and work efficiently for decades. You can also expect your property to increase in value with a solar energy system installed.

Continue Reading:

1. Solar Pathfinder – What Does It Do For You?
2. Installing Solar Water Heaters
3. Solar Panel Efficiency

If you’re living in the northern hemisphere, your solar collectors should be tilted southward. The tilt angle is 15 degrees plus the latitude of the installation site. This is the ideal configuration that allows you to collect maximum sunlight all year round. For example, Arizona has latitude of 33 degrees. Therefore the tilt angle of your panel should be 48 degrees in order for it to harness maximum energy.

But many homeowners choose to conform the tilt angle to the inclination of their roof. They are concerned about the aesthetics of the installation. Although we will not achieve an optimized configuration in an engineering point of view, such setup serves the user’s needs and wants after all.

Fortunately, solar collectors with tilt variations that fall within 20 degrees (either direction) will not suffer serious loss. In fact, tilting them some 15 degrees northward from its optimum angle can have its advantages. During summer, water will not overheat and during winter more hot water is produced.

Similarly, tilting your heat collectors southward (away from the optimum tilt angle) can result in more overheating during summer and less hot water during winter. Ideally, the tilt angle can be adjusted according to the seasons. But the hardware required to implement this setup may end up as an ugly structure of metal and joints that displease homeowners. There will also be more moving parts to be maintained.

When orientating your heat collectors, you should ideally point them to true south. As compared to photovoltaic panels, heat collectors are more forgiving. Orientations of 15 degrees off true south still enable solar collectors to receive most of the solar energy. Beyond this tolerance, the effectiveness of the heat collector decays quickly.

You may often be forced to make a choice between an east-biased or west-biased orientation away from true south. Perfect orientations tend to be impractical at times. If you’re in this fix, choose the west so heat collectors can be exposed to more heat as a result of higher ambient temperatures in the afternoons.

As you line up your compass to find true south, remember that it is pointing to magnetic south instead. Corrections must be made to locate the optimum orientation. To do this, you need to compensate for the magnetic declination of your site.

Finally, as you are evaluating the installation site, remember that shadows cause your heat collectors to be drastically less efficient. Although solar water heaters are not as sensitive to shading, it is good to place them in an open, unobstructed location from 9am to 3pm so they can be exposed to the maximum amount of sunshine during this critical period. Using a standard shade analysis tool like a solar pathfinder, you can make it easier for yourself to evaluate the shading condition of your location.

Continue Reading:

1. Solar Panel Efficiency
2. What Are Solar Heaters, How They Work And What They Are Used For
3. What You Need to Know about Solar Water Heaters