Solar panel power ratings - are they truthful?
- Category: Solar
When a manufacturer states their solar panel's power ratings, one must bear in mind that this is only a nominal reading. Unless power tolerance data is shown in the specifications, there is likely to be quite a range of possible power outputs.
Several of the solar panels we offer are made with genuine SunPower® cells which are only sold by SunPower®, directly to known manufacturers, who have passed their scrupulous inspection. And like many manufacturers, there are different grades of SunPower® cells - the higher the grade, the higher the price to the manufacturer, however the better the output. Solara and Solbian use only the geniune, high grade cells themselves on their SunPower® solar panels.
When looking at solar panels, ask to see the specification for the panels themselves. For example, Solara's Ultra glass panels show a power tolerance of -0%/+4.99%, so they are guaranteed never to be less than the nominal rating.
Charging the Meridian Northstar AGM batteries
- Category: Battery
A customer recently purchased four Meridian SPS215B AGM batteries from us for his yacht's house bank. He asked these basic, good questions:
How low can the voltage drop before starting to recharge?
Answer: Recharging when the battery gets no lower than 50% State of Charge (SOC) will result in a reasonable cycle life. For the Meridian battery, this is around 12.2 volts. Recharging at a lower SOC is possible, but will shorten the cycle life of the battery.
How fast can the battery be charged - how many amp/hours is the charger allowed to charge without damage to the batteries?
Maintenance of Flexible Solar Panels
- Category: Solar
The good news for those with flexible solar panels with a polymer top coating is that maintenance is minimal.
1. Keep the modules clean by washing them with fresh water to remove salt water deposits, bird droppings, dust particles or other debris that can lessen the chances of the sun's rays from reaching your solar cells.
The surface of the panels may be cleaned using neutral soap and water, wiping carefully and without using abrasive material. Denatured alcohol (methylated spirit) can be used to remove grease, etc.
When panel is clean and dry, apply a coating of a plastic protectorate such as "Plexus" or Novus Plastic Cleaner #1- available at your marine chandlery or online.
If contaminants build up or oxidation occurs over time, it may be necessary to polish the panel. The recommended polish is either ReJex or Novus brand polish, #2 (Fine scratch remover). It is recommended that you hand polish the panels, as a power polisher could burn the surface with too much friction. Follow the instructions on the product label.
2. Check the structural integrity of the installation and the electrical connections periodically.
3. Check the efficiency of the system using the monitoring functions in the charge regulators (LEDs or displays).
The Good, the Bad, and the Ugly: Classifying SunPower solar cells
- Category: Solar
If you see me at a trade show and notice that the company shirt I’m wearing does not fit too well around the collar, it is probably because it was bought at low cost from an outlet store by the embroiderer. The label suggests that this shirt is from a highly respected manufacturer and is of high quality, which is all true up to a point, but somehow the buttons and button-holes were mis-aligned during assembly, and so this item was sold off as a “second” or reject item in the manufacturer's outlet store.
Well, guess what? Somewhere out there is an outlet store for low grade, off-spec, SunPower® solar cells.
During manufacture, after solar cells have been tested electrically they are sorted into different “Bins” dependent on how they performed. Some will be over achievers and be put aside for research purposes, while others will simply fail miserably and be destroyed. Those remaining are the Good, the Bad, and the Ugly cells; Good being “Prime”, Bad being “Off-Spec”, while the Ugly cells will have visual or cosmetic defects.
The Prime cells are further graded into High, Premium, and Ultra performance categories, while the Off-Spec cells are