The Revolution in Solar

The Revolution in Solar

New technologies may be on the verge of disrupting century-old electric utilities. Blockchain financing, storage, lowered prices as well as new technologies and designs are bringing affordable, beautiful and economical solar to houses and industries across the nation.

Solar Microgrids: The Brooklyn Microgrid

Traditionally, solar panel arrays require a relationship with the local electricity utility. When the home is using more power than created by solar panels, the homeowner pays the utility for grid electricity to supplement their solar production and meet the energy needs of the household. But when the solar panels produce more electricity than the home uses, the electricity is fed into the grid and the homeowner is credited by running their electricity meter backwards, effectively reducing their electricity bill. This practice of running the meter backwards is known as net metering, where the homeowners are only changed for the difference between the energy that they buy and the energy that they sell back.

The grid is the network of power lines that distributes electricity from a centralized power plant to buildings and homes. Utilities charge customers for the amount of electricity that they use, and bill consumers at the end of the month. A new proof of concept project called the “Brooklyn Microgrid” in New York City challenges the entire grid model of electricity distribution. In the Park Slope neighborhood of Brooklyn, residents are bypassing utility companies completely and selling electricity produced by personal rooftop solar panels to one another.

Audrey Zibelman“It takes a central procurer — in this case, historically, the utility — out of the mix,” said Audrey Zibelman, renowned for electric grid management, and former chairwoman of the New York State Public Service Commission, which regulates the state’s utilities. “Community members can work both individually and collectively to help meet demand in an efficient way. It really sets the market where they’re not buying and selling to the utility but they’re identifying each other’s need and willingness to buy and sell.”

Compared to this traditional model, the microgrid being used in Brooklyn allows residents to bypass this utility managed net metering process, buying and selling directly within the community. The company running the project, LO3 Energy, created a hybrid electricity meter and computer device called a TransActive Grid Element. Residents who are part of the network each have their own personal hybrid node device installed, which connects residents to each other and allows the system to work. 

Blockchain

TransActive Grid ElementThe process that that powers the microgrid in Brooklyn is called Blockchain, which uses the same technology as bitcoin. Blockchain allows node devices within the system to buy and sell electricity between each other automatically, based on user preferences. The system acts as a decentralized database connecting all users on microgrid, with no central control center. Those with solar panels feed electricity into the grid through a blockchain enabled meter and the flow of energy is automatically recorded. Then algorithms match buyers and sellers in real time based on preferences, and record the planned transaction. The buyer then automatically pays the seller once the set amount of electricity has been delivered. The key concept of blockchain is that during each step of the process, everything is being recorded on not just the nodes of the seller and buyer, but is also recorded onto every node on the network. This self authenticating process lets all the nodes on the network verify all transactions, and ensures that records can not be altered.

As part of New York State Governor Andrew Cuomo’s Reforming the Energy Vision plan to make the grid more resilient in the wake of Hurricane Sandy’s wide scale blackouts, research into local grids and community participation was encouraged. Microgrids could be a key element in a future where electricity could still be available during a wide scale blackout or other emergency. Decentralized energy distribution technology benefits users and holds great potential for similar solar networks in the future. Because residents sell to their neighbors, the electric utility is cut out of the picture entirely; reinventing the way we power our communities. The renewable, local, nature of the microgrid provides lower electricity costs and increased energy efficiency for all residents involved.

Solar Energy Storage: Tesla Battery Banks

Tesla powerwallBattery systems provide game changing potential to solar systems, allowing solar generated during the day to be used during the evening and night when electricity costs peak. Tesla, famous for their electric cars, has been looking to innovate in solar technologies after buying SolarCity in 2016. In the past year, Tesla Energy began selling the first home battery system called Powerwall with direct emphasis on consumer ease of use, mass adoption, and direct integration with a home solar panel system.

The system can store excess solar energy during peak generation, and then supplies the home with clean energy at night when generation falls. According to Tesla, another benefit is load shifting, where by charging during low rate periods when demand for electricity is lower and discharging during more expensive rate periods when electricity demand is higher, the system can automatically lower energy costs. Home battery systems have the added benefit of providing backup power during an outage, or even supply a home completely off grid through solar panels and battery systems.

peak solar

Battery systems also have the potential to be scaled up to commercial or even utility level sizes, bringing the same benefits of smaller residential systems but for grid operators.

  • Reduce peak load on the grid by feeding stored power into the grid when needed.
  • Act as a buffer while waiting for a large generation source to ramp up or down
  • Improve customer power quality by preventing fluctuations in electricity availability.
  • Help renewable sources by filling any inconsistency of power from these sources and storing excess capacity until it is needed.

Increased adoption continues to drive down cost.

The biggest improvement in solar may be rate at which the world is adding new solar capacity, and the rate of new solar installations. The world continues to produce solar panels at an increasing rate, which in turn drives costs down, due to the economics of scale. The U.S. Department of Energy's Lawrence Berkeley National Lab found in 2013 that the cost of solar cells had decreased by 80 percent from 1998 to 2012.Similar to Moore’s Law, Swanson's Law is an observation that the price of solar modules tends to drop 20 percent for every doubling of total shipped volume of solar panels. Generally, this means the cost of solar panel capacity drops by 10% every year. Crystalline silicon solar panel prices have fallen from $76.67 per watt in 1977 to $0.36 per watt in 2014.  The falling cost of solar panels touches every other aspect of solar, from widespread and proven home installations, to new solar panel designs on the cutting edge.

The ability to produce more solar capacity and drive the cost of solar energy down could be the biggest technological advantage of solar when looking towards the future of power generation. No other source of electricity has its costs drop in such a drastic, predictable, way as capacity is added. As production increases in the future, solar has the potential to undercut the cost of other forms of generation.

New Solar Panel Innovations

Incremental upgrades are continuously developed every year that aim to increase conversion efficiency, or the percentage of sunlight converted into electricity by the cell. Market driven, companies are also finding breakthrough innovations in the way we use solar panels, hoping to utilize solar to its fullest potential.

Bifacial solar panelOne example is double-sided solar panels being made by manufacturers like LG and SolarWorld. Double-sided panels can harness sunlight through both surfaces of the panel, capturing light as it reflects off the roof or ground below the panel. When mounted on roofs, white paint is applied during installation to maximize reflected light and therefore energy generation. In the case of ground mounted solar, the light will naturally reflect off the ground providing increased production. The effect is amplified greatly during the winter if the ground snow covered, greatly increasing the amount of light being reflected to the underside of panels. This panel design can offer up to a 25% increase in power output annually.

In Isawa Japan, solar installer Ciel & Terre created a solar farm attached to an array of floats sitting on top of a local water reservoir. In addition to generating electricity, water based floating solar arrays can reduce algae growth and the rate of evaporation. The solar panels themselves benefit from the cooling effect of the water, increasing panel performance. Another example that uses similar technology is a new panel system called CoolPV can both heat water and create electricity. Dark, heat absorbing, solar cells produce electricity, and tubes under the panel surface remove excess heat and warm the water. Because the water removes heat, the panels benefit from the same increased energy production due to cooler panels as the floating solar farm installation in Japan.

Design Improvements

Tesla solar roof glass tilesIn some residential solar installations, esthetic improvements to solar panels may be as important as technological improvements. People are generally more willing to invest money into something that they like to the look of, and while some may like the look of traditional solar panel roof installations, others may find it unappealing. Homeowners already pick paint colors, roof colors, and home fixtures, so it is easy to imagine being able to choose a style of solar panel. Recently Tesla started to offer a “Solar Roof” where instead of traditional roof material and mounted solar panels, the roof itself is made of individual glass tiles with integrated solar cells. The design closely mimics the styles of traditional roofs but with the benefits of integrated solar. Additionally, the solar glass tiles are so durable compared to traditionally roof tiles, that they are warrantied indefinitely. Some solar installers are beginning to offer “low profile” solar panels that are designed to be more subtle.

Solar Revolution

Each one of these new technological innovations plays a part in transforming the way we interact with electricity. On its own, microgrid technology has the potential to significantly impact utilities, allowing more people and businesses to be independent from the grid. Solar panels themselves are becoming more economical, as conversion efficiency goes up and cost goes down. Home batteries allow for the total utilization of home solar energy, enabling the storage of generated electricity. Which of these innovations take hold and which fade away depends on more than just the technology alone, and it may take years to see what trends emerge. The combination of these new technologies has the potential to re-imagine our current system while ushering in clean energy.