The National Renewable Energy Lab’s Flatirons Campus is home to the National Wind Technology Center in Arvada, Colorado. On the campus, there are a few research turbines for studying more efficient blade design, powering capabilities beyond just the campus (feeding back to the grid) and early detection of birds via radar to avoid collisions.
Wind turbines work by using the force of the wind to turn the blades, which in turn rotate a shaft connected to a generator. The shape and angle of the blades are designed to capture as much energy as possible from the wind. The generator produces electricity by using the rotational energy from the rotor to produce energy and then that energy can either be used immediately, stored in batteries, or fed into the electrical grid. Wind turbines also are equipped with sensors that monitor wind speed and direction, as well as the performance of the turbine. The control system in the turbine can adjust the angle of the blades to optimize the amount of energy being captured from the wind as the wind speeds change.
The cost of wind energy has been declining over the years and is now competitive with conventional sources of energy. However, the initial cost of installing a wind turbine can be high, with a typical cost of $1.5 million to $2 million per megawatt (MW) of capacity. On the other hand, the cost of solar panels has been declining rapidly, and is now one of the most affordable sources of renewable energy. Another area of research at this NREL campus is bifacial panels, which work by having a layer of photovoltaic (PV) cells on both sides of the panel. When sunlight hits the front of the panel, the PV cells convert the energy from the sun into electricity. Some of the light that hits the panel is also reflected back onto the rear surface of the panel. Bifacial panels capture this reflected light, which also generates electricity. These panels can be mounted in a variety of ways, including on the ground, on rooftops, or as part of a solar tracking system. They are particularly effective in locations where there is a lot of diffuse light, such as cloudy or hazy environments, or where light reflects off surfaces like water or snow.
While wind turbines and solar panels have different costs, both can be effective at generating renewable energy and reducing greenhouse gas emissions. Ultimately, the choice between wind turbines and solar panels will depend on factors such as the available wind and solar resources at a particular location, as well as local policies and regulations related to renewable energy.
photo: Ulyana Peña, on-site at NREL Flatirons Campus