Denmark May Hold the Key to Integrating Large Amounts of Intermittent Renewables

A team of Finnish engineers havevinstalled the first commercial battery made of sand, which can store green energy in it for months. Solar panels or wind turbines generate electricity, which is then stored as heat in the sand battery. When needed, the battery can discharge hot air to heat up water which is then used to heat homes, offices, and a swimming pool. This solution may be difficult to scale, but it’s a low-cost storage idea that could be useful when it’s cold and energy is more expensive.

One of the greatest challenges to integrating renewable energy sources into the power grid has been the issue of storage - where and how to keep power generated during off-hours (such as overnight) when demand is low. While batteries are on the rise as one solution, an Alabama power plant has discovered a natural way of storing energy until it is needed: pumping air into salt caverns.

Dams make for complex and often controversial infrastructure. While hydropower generated from large dam projects is currently providing the bulk of the planet's renewable energy, dams can also cause major environmental and social damage by interrupting animal migrations, displacing indigenous communities, and collecting toxins. A number of solutions are being implemented, however, to address the various issues caused by dams, to help make them a more eco-friendly and viable source of clean energy.

Micro-hydro projects in the United States have become much more accessible and more financially viable since Congress passed a law in 2013 making it easier for small hydroelectric projects to get federal approval. Specifically, water treatment plants that can retrofit their systems to generate electricity are an excellent energy opportunity. The plant in Grand Lake now produces more electricity than it consumes.

Solar power is an important renewable energy in Germany, but when the sun is out, it can overpower the grid. Likewise, when the sun is not out, the reception of solar power decreases. Germany has piloted battery installations that store solar energy for use when the sunlight is not plentiful and has successfully incentivized citizens to use them to lower costs.

A collaborative partnership among local and national organizations made it possible to install solar panels on 10 Greensboro homes for free. Because of this effort, many low-income families have seen a significant decrease in their energy bills and an increase in value of their homes. Although convincing people to install the panels was a challenge, organizers are now figuring out how to scale the initiative and make it sustainable in the longterm.

Over 70 Catholic dioceses in the Philippines have entered into an agreement with energy resource company WeGen Laudato Si to install solar panels on their parishes, schools, and other buildings. The Diocese of Maasin on Leyte Island became the first in the world to completely shift to renewable energy. Installing the panels can be expensive, but shifting to solar has saved one diocese at least 100,000 pesos a month in energy bills.

An apartment complex in Utah includes a solar battery in every apartment allowing the resident, power utility, and building developer to save costs for generating electricity. Through a unique partnership, the power systems can provide 12.6 megawatts of power for the building, which translates into residents saving up to 40 percent on the energy bills. This setup might not be easy to scale, but the developer plans to expand the model in other states.

Mosques across Amman, Jordan are adorned with solar panels, resulting in some very energy efficient places of worship (along with many other buildings). The mosques now cover 100% of their energy needs and can even sell excess energy back to the national grid. The city is aiming to become carbon neutral by 2050, and in addition to recycling, environmental education, and solar water heaters, Amman is expanding their ecotourism industry to attract more environmentally conscious tourists.

Rahr Malting, a brewery in Shakopee, MN, has found a creative way to sustainably address their energy needs. The company partners with the Mdewakanton Sioux Community to use waste barley hulls from the malting factory to generate electricity for their facilities, selling excess power to the public grid while the waste heat sprouts the malt to make beer.