Posts Tagged solar power

Solar Electric Charging Stations in California

Posted by on Thursday, 15 July, 2010

Electric cars are a sustainable alternative to petroleum powered cars, since electric cars do not need a constant supply of gasoline or diesel to fuel them. One of the major issues with powering electric cars is the sustainability of their power supply, as charging an electric vehicle from a wall socket likely means that the car is using electricity generated by coal plants or other nonrenewable sources. In addition, electric generator stations are not available in many locations.

A partnership between the solar company Solar City and Rabobank provides solar power to many California residents. Rabobank is assisting in two ways, it is financing construction of solar power generation facilities, and it is setting up electric power charging stations at bank branches. Many banks offer their customers pens, I don’t know of any that offer their customers a place to refuel their cars. The Rabobank locations offering power generation are in locations such as Atascadero and Salinas, along the coast and inland area following Highway 101 in Central California. Central California includes many long stretches of highway where cities and gas stations are rare and it could be 30 miles before reaching the next station, so this is very useful to drivers of electric vehicles which may have a shorter range than gas powered vehicles. There are plenty of electric charging stations in Los Angeles and San Francisco, so providing a charging station halfway between the cities is the logical step. According to Rabobank, there will be six power generation stations in Central California producing a combined 200 kilowatts of solar power to charge electric cars’ batteries.

This charging station project is also operating with the assistance of Tesla Motors, an electric vehicle manufacturer. According to Tesla Motors, Solar City already builds electric chargers for home charging of Tesla Motors cars. The partnership ensures that these charging stations are designed to operate with existing electric vehicles available on the California market. Although Tesla mentions that these stations are in populated locations, most of these towns are extremely small compared to the densely populated Southern California and Northern California locations. Adding locations in Goleta, Watsonville, Salinas, and a few other cities cuts the distance between charging stations to around 60 miles as far as I can tell which should provide plenty of leeway. It would be interesting to see charging stations on the northern section of 101 up to Portland. Although much of the area is heavily forested, people up there are environmentally conscious enough to make it work. Arcata has an electric charging system already, so chargers in the Mendocino region would be the most helpful.

Big Box Retailers and Solar Power Generation

Posted by on Thursday, 10 June, 2010

Researching the Solana plant led me to a Senate report on solar power generation. Big box retailers such as Walmart, Target, and Best Buy have huge stores, many of which are located in the hot Southwest. Some of these stores have large quantities of food which must be refrigerated, and they may also air condition their stores for customer comfort. This requires a lot of power, and the 2008 gasoline price spike scared a lot of companies into setting up their own renewable power generation systems. The big box stores are now installing their own solar photovoltaic equipment.

Walmart has installed a large solar array at its location in Apple Valley. This project now provides 1 megawatt of solar power to run the Apple Valley Walmart. It’s part of a larger Walmart initiative, Walmart already set up 18 solar arrays at stores in California and plans to have as many as 40 arrays complete in California locations by the end of 2010. These arrays are intended to provide about a quarter of the power that a store uses, and Walmart claims that its goal is to eventually switch fully to renewable power sources.

Many of the big box chains also sell solar panels and control equipment. Chains that focus on electronics and related equipment, such as Fry’s Electronics, have the best selections of solar gear. Larger store chains like Costco and Walmart that sell pretty much anything also sell solar power setups. Rebates on this equipment may be available as well.

Costco is also installing large photovoltaic systems at its own store locations. One of the biggest installations is at a Costco in New Jersey. Solar Power, Inc performed this installation, with solar panels manufactured by the Bay Area firm Solyndra. Solyndra and Solar Power, Inc won an award from Renewable Energy World for the successful completion of this project. The Solyndra solar collectors include significant technological breakthroughs since the cylinders in the panel can collect solar rays from any direction, providing efficiency improvements. President Obama and Senator Barbara Boxer have toured Solyndra’s Fremont solar panel factory, and Solyndra has received federal loan guarantees to continue solar panel construction.

Target is another large big box store that sells solar panels and other appliances which can be recharged by the sun. Some Target stores also have their own solar installations now. According to Target, the company has 21 stores in California with solar power systems installed and plans to add more. The company mentions that earlier stores may not be designed for solar panel installation on their roofs, although new roofs can incorporate this goal.

The Solana Installation of Arizona

Posted by on Thursday, 10 June, 2010

In the desert of Arizona, a large new solar plant is under construction. According to its builder, the Spanish firm Abengoa, this will be the largest solar installation in the world, a 280 MW project which will begin construction in 2011 and reach completion in 2014. There are larger projects under construction in China although they are also not complete.

As with other large scale renewable energy projects, the Solana Installation receives loan guarantees from the federal government. This ensures that this solar project has the funding to continue its development. When the plant is complete, Abengoa intends to sell the power it generates to the Arizona Public Service, which is a state government run utility.

Solana is a type of power plant known as a Concentrating Solar Power project. This project concentrates energy collected from direct sunlight. According to a presentation given to the USDA, some solar collectors require direct energy from the sun and others can pick up diffuse energy reflected from other surfaces. A concentrating solar power plant requires direct sunlight to operate, and there are few better places to collect direct sunlight than the deserts of Arizona. The Solana installation requires 1900 acres to set up the solar plant, and there is space available in the red desert.

The Solana installation includes parabolic troughs which concentrate the sunlight. These appear as mirrored canals with a pipe running through the middle of the trough. The power plant collects the energy and can use it to melt salt. Molten salt storage is very useful since it allows a solar plant to store energy and release it into the grid for several hours at night.

Arizona, like other states including California, requires its power producers to meet renewable power generation goals in the future. According to the Arizona Corporation Commission, Arizona requires 15 percent renewable energy generation by 2025 for utilities that operate in the state. Arizona currently gets about 40 percent of its power from coal and the rest from natural gas and nuclear power, according to the Department of Energy.

Solar Power in the Spanish Night

Posted by on Sunday, 18 April, 2010

Recently some Spanish business organizations have questioned the reports of Spanish companies that reported solar power production at night. They thought it might be fraud, although there are ways of generating solar power at night.

An article by Business Week reported this story. The business group ASIF demanded an investigation. There actually are ways to produce solar power at night. According to the University of Central Florida, solar power can be produced at night. Students at the school found a method of storing solar energy in wax. Since the wax remains liquid even after the sun sets, it continues to hold heat energy that is used to heat hot water.

It’s not just wax that can be used to store solar energy at night. Researchers at Yale University have reported a method of storing solar energy using molten salt. Surprisingly enough, this method of storing solar energy in salts such as potassium nitrate is used in Spanish solar thermal plants, according to the Yale article. Since this technology is already available in Spain, the solar power companies in Spain have already implemented methods of using solar power at night. This information should alleviate the concerns of Spanish businesses who feel they are being charged for solar energy at night and being provided energy from petroleum based sources, by demonstrating that this method is already in common use in Spain.

Some of the Spanish solar thermal plants are very large. The University of Montana shows an array of hundreds of mirrors which reflect the solar energy. The mirrors can heat a substance to several hundred degrees Celsius. It is important to select the correct substance to contain this energy. A wax that melts easily at a hundred degrees may boil away if heated too hot. It’s also necessary to select a substance that contains a large amount of heat energy. Water is capable of storing large amounts of energy, although it does boil or evaporate if exposed to too much heat. The University of Montana suggests that graphite compounds are another potential material for storing the heat energy in solar thermal plants.


Posted by on Thursday, 11 March, 2010

I have seen a lot of technologies based on nature recently. The axiom always said not to reinvent the wheel, so why would we attempt to do this when creating sustainable business? Anything that powers a living organism has been shaped by evolution over many years. Because of the competitive pressures in any environment, superfluous elements are swept away. Even things that seem like they have no purpose like the peacock’s feathered tail and the songbird’s song are necessary so that the creature can attract potential mates. Resources are limited, so many animals have evolved to become efficient in surprising ways. Here are a few companies that are attempting to harness these natural processes to gain a competitive advantage.

On the White House energy blog, Secretary Steven Chu mentioned some of the companies that received the ARPA-E grants to help them research new technologies. One of the companies he mentioned was Sun Catalytix. They got a $4 million grant to research an energy process which is similar to photosynthesis. All of the other energy sources are originally powered by the sun, and it will continue to be the main source of energy in the future. Photosynthesis has beaten out all of its competition so far, so it definitely appears to be the ideal place to start looking for a new direction.

We have the advantage of not needing to power the other parts of a tree, such as organs used for defense and reproduction, and so we can focus in on the conversion of as much energy as possible from the reaction. The Sun Catalytix site links to which gives a little more information on the technology. This article talks about the catalyst forming and operating in neutral water under ambient conditions. It also mentions that the catalyst is formed from common materials; many efficient solar power devices require the use of rare earth metals, and we could quickly run out of them if we tried to set up many large scale power plants using rare earth metals. Mining is also a large potential issue with solar technology as extracting metals often causes a lot of damage. Biomimicry reduces a lot of the problems caused by mining, as a tree does not need to destroy an entire mountain to be able to gain its nutrition from the sun.

The biggest issue I see with biomimicry is the complexity of the molecules used in the new technologies. A lot of traditional chemistry reactions can be explained very simply, you have a process like H2 + O2 → 2H2O. Even the other reactions like burning petroleum are not much more complex, you have a reaction like CH3-CH2(n)-CH3 + O2(excess) → CO2+H2O. There are some contaminants like nitrogen and sulfur that are burned and create smog, but that’s how the main reaction goes. For a biological reaction you’re attempting to mimic molecules that are a lot more complex. Look at the structure of Chlorophyll, it is a lot harder to model the reactions of a molecule this complex. Fortunately, with the software we have available now it is becoming much easier to calculate the molecular interactions, and once the research is complete building additional solar plants based on biomimicry should be a lot cheaper than having to dig up rare earth metals.