Photovoltaic system in northern climes to 5.61 kWh/m²/day in the sunniest regions. For large systems, the energy gained by using tracking systems can outweigh the added complexity (trackers can increase efficiency by 30% or more). For very large systems, the added maintenance of tracking is a substantial detriment. Tracking is not required for flat panel and low-concentration photovoltaic systems. For high-concentration photovoltaic systems, dual axis tracking is a necessity. Pricing trends affect the balance between adding more stationary solar panels versus having fewer panels that track. When solar panel prices drop, trackers become a less attractive option. Systems designed to deliver alternating
Photovoltaic keyboard Photovoltaic keyboard A photovoltaic keyboard is a wireless computer keyboard that charges its batteries from a light source such as the sun or interior lighting, addressing a major drawback of wireless computer peripherals that otherwise require regular replacement of discharged batteries. The Logitech K750 has a set of photovoltaic cells on the top edge, charges in sunlight or under a standard bulb, can work up to three months in total darkness, and includes software to display battery charging status. It is a fullsized keyboard, including the usual movement keys and NumPad section on the right side, with low-profile keys much