Forgot Password

  • en
  • ru
  • fr
  • fr
Currency :

Freeshipping on order over $100

Lorem Ipsum is simply dummy text of the printing industry.

10% off the bill

Lorem Ipsum is simply dummy text of the printing industry.

Have a Question

Contact us Now. Call a Specialist or Chat Online. Call 1-800-EARTH0

Get help

Lorem Ipsum is simply dummy text of the printing industry.
Earth-0 E0-B12-Flat-Roof-Solar-Panels-Mount

Ballast is a common alternative used on solar installations unable to penetrate either the roof or the ground. On low-sloped, flatter rooftops, many building owners don’t want to poke holes through the roof. Temperamental ground-mounts have some of the same concerns; solar arrays installed on top of landfill caps cannot penetrate that liner.

That’s where solar ballast comes in. Concrete blocks are placed throughout a project to secure an array to the ground or the roof and prevent wind lift or other movement, all without having to make any (or as many) penetrations.

An Earth-0 project utilizes ballast blocks.

First there are many factors that go in to determining how much ballast a solar array needs. Most are pretty obvious: size and orientation of array; physical project location (wind, seismic factors); roof shape, height and strength; and type of racking used.

Common rectangular-sized ballast blocks can be purchased at a home improvement store or anywhere that carries masonry blocks. The sources for unique block shapes and sizes specific to a certain racking system are provided by the racking manufacturer.
The racking design will dictate the maximum size of ballast blocks that can be used.

A system should be able to hold multiple blocks in each ballast pan such that weight can be added to or subtracted from a specific spot on the array. This is necessary because ballast weight isn’t always uniform throughout an array. More weight may be required at corners or specific areas compared with other areas.

The core element of ballast—concrete blocks—hasn’t changed much since the beginning of solar installations. But project and racking design has led to the biggest evolution in ballast—less is best. By using wind tunnel analysis, the amount of ballast weight needed on today’s solar projects is less than before. Changing how panels are interconnected allows for increased load sharing and an overall drop in needed ballast. Racking companies incorporating wind deflectors makes an array more aerodynamic and less ballast is needed to hold everything down.

An emerging issue with solar ballast is the breakdown of the concrete. Common concrete landscaping pavers can deteriorate through exposure to UV light, moisture and freezing/thawing.
Broken chunks of concrete on the roof can damage the roof membrane—maintenance personnel step on the pieces, grinding or tearing the roof membrane.

It is recommended to ensure solar installers use concrete that has the appropriate rating for the local environmental conditions. Concrete is available in a range of ratings and quality levels, so a little homework can lead to years of solar success. Using high quality racking components also helps with ballast installations
While there have been ideas for alternative ballast materials (jugs of water have been considered), concrete ballast isn’t going anywhere any time soon. Essentially simpler to install than penetrating systems—mostly from fewer pieces of hardware and less skill needed—ballast systems do require some technical know-how.

With the right dedication to installation precision, ballasted solar systems can be a successful alternative to penetrating systems.

Engineers at Oregon State University have identified a new approach for the storage of concentrated solar thermal energy, to reduce its cost and make it more practical for wider use.

The advance is based on a new innovation with thermochemical storage, in which chemical transformation is used in repeated cycles to hold heat, use it to drive turbines, and then be re-heated to continue the cycle. Most commonly this might be done over a 24-hour period, with variable levels of solar-powered electricity available at any time of day, as dictated by demand.

The findings have been published in ChemSusChem, a professional journal covering sustainable chemistry. The work was supported by the SunShot Initiative of the U.S. Department of Energy, and done in collaboration with researchers at the University of Florida.

Conceptually, all of the energy produced could be stored indefinitely and used later when the electricity is most needed. Alternatively, some energy could be used immediately and the rest stored for later use.

Storage of this type helps to solve one of the key factors limiting the wider use of solar energy – by eliminating the need to use the electricity immediately. The underlying power source is based on production that varies enormously, not just night and day, but some days, or times of day, that solar intensity is more or less powerful. Many alternative energy systems are constrained by this lack of dependability and consistent energy flow.

Solar thermal electricity has been of considerable interest because of its potential to lower costs. In contrast to conventional solar photovoltaic cells that produce electricity directly from sunlight, solar thermal generation of energy is developed as a large power plant in which acres of mirrors precisely reflect sunlight onto a solar receiver. That energy has been used to heat a fluid that in turn drives a turbine to produce electricity.

Such technology is appealing because it’s safe, long-lasting, friendly to the environment and produces no greenhouse gas emissions. Cost, dependability and efficiency have been the primary constraints.

“With the compounds we’re studying, there’s significant potential to lower costs and increase efficiency,” said Nick AuYeung, an assistant professor of chemical engineering in the OSU College of Engineering, corresponding author on this study, and an expert in novel applications and use of sustainable energy.

“In these types of systems, energy efficiency is closely related to use of the highest temperatures possible,” AuYeung said. “The molten salts now being used to store solar thermal energy can only work at about 600 degrees centigrade, and also require large containers and corrosive materials. The compound we’re studying can be used at up to 1,200 degrees, and might be twice as efficient as existing systems.

“This has the potential for a real breakthrough in energy storage,” he said.

According to AuYeung, thermochemical storage resembles a battery, in which chemical bonds are used to store and release energy – but in this case, the transfer is based on heat, not electricity.

The system hinges on the reversible decomposition of strontium carbonate into strontium oxide and carbon dioxide, which consumes thermal energy. During discharge, the recombination of strontium oxide and carbon dioxide releases the stored heat. These materials are nonflammable, readily available and environmentally safe.

In comparison to existing approaches, the new system could also allow a 10-fold increase in energy density – it’s physically much smaller and would be cheaper to build.

The proposed system would work at such high temperatures that it could first be used to directly heat air which would drive a turbine to produce electricity, and then residual heat could be used to make steam to drive yet another turbine.

In laboratory tests, one concern arose when the energy storage capacity of the process declined after 45 heating and cooling cycles, due to some changes in the underlying materials. Further research will be needed to identify ways to reprocess the materials or significantly extend the number of cycles that could be performed before any reprocessing was needed, AuYeung said.

Other refinements may also be necessary to test the system at larger scales and resolve issues such as thermal shocks, he said, before a prototype could be ready for testing at a national laboratory.