With energy costs on a constant climb and global warming an unequivocal fact, everyone is looking for a less expensive and more environmentally friendly way to get their energy. Paving the way are options like geothermal heat, solar power, biofuels, wind power, and nuclear energy. Beginning with the oil crisis in 1973, the US government began investing heavily in renewable energy research and development in an effort to develop alternative power sources. Solar power has become one of the more accessible and affordable ways for the average person to join the battle of sustaining earth’s atmosphere while wind power has picked up speed with businesses, especially with electricity and water companies.
But how does solar power actually work? Solar power works similarly to the photosynthesis process of a plant. The big difference being that plants absorb the sunlight and also pull CO2 out of the air to create its energy. If solar cells could also pull CO2 out of the air, they would be a tremendous benefit to the our current global warming issues. In simple terms, solar power works by a solar cell absorbing the light from the sun, which causes one of the bonds’ electrons to excite to a higher energy level and freely move around, creating an electrical current ripe for harnessing.
Just like the sun’s light hitting your skin makes you feel warm, the sun’s light hitting certain compounds creates an electrical current. Photovoltaic, PV, cells convert sunlight into direct current (DC) electricity. An inverter then converts the DC into AC electricity which in turn powers through an electrical panel to appliances, lamps, etc. To help understand further, the word photovoltaic is a combination of the terms photons and voltage. Photons are the basic unit that makes up all light and voltage is electromotive force, or electricity.
Solar Power Origins
Edmond Becquerel was a nineteenth century French physicist who researched magnetism, electricity, and optics: phosphorescence and luminescence interested him most. In the 1840s he discovered that exposing certain substances to light caused chemical reactions that could produce an electric current in metals and liquids. Building an actinometer he was able to measure the light source’s intensity through the amount of electrical current elicited in the substances. This light energy and chemical energy connection was embraced by many scientists following him but none advanced the field significantly until 1940 when Russell Ohl, working for Bell Labs, patented the first solar cell.
Russell noticed that when his cracked silicon sample was exposed to light, the current between the two sides of the crack saw a significant jump. Sunlight was being converted to electrical energy and Ohl had invented the silicon solar cell. The silicon cell was much more efficient than the previous selenium solar cells and AT&T linked a group of solar cells creating a solar battery. This battery was able to power a small electrical circuit that was mounted onto a telephone pole.
Solar power equipment and infrastructure experience their own challenges: overheating, dust contamination, water ingress, and EMI attenuation. While addressing these issues with filters, you must consider compliance with industry standards and environmental regulations. The equipment needs to be protected with proper filters. Engineered air filtration solutions will not only save you money, but will enhance your system’s energy efficiency.
You can improve a solar power system’s reliability, durability, and safety with the correct air filters, EMI vents, mist eliminators, and screens. Universal Air Filter not only carries products appropriate for solar power equipment and EMI shielding equipment protection, but their filters are suited for indoor and outdoor applications, even in harsh environmental conditions. UAF creates custom filters for every situation and addresses every requirement, even creating prototypes to field test.
The solar power system depends on AC or DC converter or inverter. Basically, the DC supplied by the solar panel is switched on and off to provide the power line frequency. On both the AC and DC sides of the conversion, the efficiency and performance can be detrimentally affected by various noise sources. Microcontrollers from sophisticated electronics improve the AC signal purity. The operation of the sensitive electronics of the power converter at the AC output can be harmfully influenced by broadband interference spectrum and harmonics that can cause noncompliance with utility codes and power-quality standards, fail compliance testing for EMC (electromagnetic compatibility) completely, or experience total equipment failure. On the DC side, leakage currents and electromagnetic interference (EMI) radiated by the panels can cause premature aging of the panels.
Inverter output signals need to be pure sine wave and devoid of harmonics or high frequency components. This can only be achieved with proper filtering. For peak performance, a DC EMC filter is essential, an AC EMC filter on the output side is recommended, and a sine wave filter is a helpful addition.
Wind turbines extract energy from the wind by capturing the wind’s kinetic energy and converting it into electrical power. The wind spins/rotates the turbine blades, which capture the kinetic energy of the wind by transferring the energy into the spinning shaft, converting it into a rotary motion through the shaft driving a generator and making electricity. The two basic designs of wind turbines are horizontal and vertical axis wind turbines. Horizontal (or HAWT) are most common, displaying the propellers like a household fan, while the vertical (VAWT) looks more like an egg beater.
Wind speed and size of the blades are the key factors to the available power that can be harvested from the wind. The faster the blades spin, or the greater the area swept by the blades, increases the amount of extractable energy.
Wind Power Origins
Wind has been used as a power source for thousands of years in the form of sailboats and windmills. Somewhere in 500-900 the Persians and Chinese used wind powered grain mills and water pumps. The first windmills were four blades and a tail or weathervane to turn into the wind. Daniel Halladay is credited with the first manufactured windmill in the US in 1854. The first electricity generating wind turbine was invented in 1888 in Cleveland, Ohio by Charles F. Brush. Containing 144 wood rotor blades with a 50 foot diameter, the windmill generated 12 kW of power.
Today, wind power can cost as little as $35 per megawatt hour MWh, which is significantly less than the $50 per MWh of natural gas and still lower than the $37 per MWh of coal. Of course, the financial savings is just one benefit, as both coal and natural gas are nonrenewable energy sources, the exploration and extraction of them costs us much more due to the environmental impact.
Wind Power Issues
More than 75% of running wind turbines are constructed with gear systems containing lubricating gear oil. Older turbines do not have filtration systems and the contamination buildup in the system stays in the system and on the gearbox, generating even more contamination.
Newer wind turbines generally have an oil filter in the gear oil cooling system. Keeping the oil temperature low requires a filter with proper efficiency. Because oil types used in the gearboxes are high viscosity gear oils like mineral, semisynthetic and synthetic, a filter pump with a bypass valve tested down to negative 30 degrees Celsius is generally necessary.
Universal Air Filter for Renewable Power Systems
Specifically addressing the issues associated with both solar and wind power equipment, Universal Air Filter is creating new designs that will withstand the harsh environments of these outdoor systems. To reduce maintenance and prolong the life of a system and the filters within it, UAF has recognized stock filters can’t always perform as needed and they are working on filters with higher durability and made of different materials. Currently, many filters are made of a cardboard frame and polyester media which is neither washable nor enduring. Exposure to high winds, blowing dust, and wind-driven rain, cause standard, commodity air filters to prematurely fail in the field. Utilizing cost-effective designs incorporating sturdy aluminum frames and rugged filter media, UAF is aiming to service equipment and improve performance for their wind and solar customers more effectively.