Tag Archives: PV electric

Scalability in Energy Production.

Scalability is the capacity to expand production as the need for additional power comes to the fore. A nuclear power plant can take years from the time of initial planning, permitting, and construction, whereas installation of solar panels for a home array will take only a couple of days. The material and labor costs during the construction or installation phase raise the cost of the power source over the cost to fuel and operate the facility once completed.

For necessarily large projects like nuclear or hydro-power facilities, long lead times are needed to bring power on line. This means that planning and construction must begin long before the power is available. This has considerable monetary cost because money is spent year after year before any money comes in from the sale of the power after completion.

An unpredictable risk inherent in the long term, big projects is that conditions may change. A steep drop in the economy during the recent “great recession” resulted in decreases in demand for energy world wide. Changes in technology, particularly with power sources which are more scalable may make a large project obsolete. Natural gas turbine technology is quite scalable. Turbines designed for jet aircraft can be used to generate electricity. The advent of directional drilling and fracking has greatly increased the availability and lowered the cost of natural gas which fuels scalable gas turbine facilities. Planning and construction of large scale coal plants are being canceled left and right.

Our economy is slowly recovering from the recession and new power sources are needed. Scalable power supplies are rapidly replacing large projects because they can reliably deliver power when and where it is needed and at a lower cost.

Solar power is booming across the country. Solar PV is growing 17 times as fast as the economy as a whole. This is due in large part to its scalability. If you need a little power, use just a few panels, such as what be need to charge the batteries on a remote cabin or an RV. To power the average home requires about 20 or 30 panels (10 kilowatt system which can produces 1100 kWh per month.)

For utility scale solar the numbers can get quite large. A one megawatt facility in Benton AR just went online. It employs 3,840 panels on a 5 acre site. The largest planned in Arkansas is an 81 MW, 500 acre facility with 350,000 panels. The country’s largest array not surprisingly is in California. At 550 MW, the array of over 2 million panels will power close to 100 million homes.

Wind is similarly scalable except at the lowest end of the spectrum. Modern wind turbines for utility scale facilities are 2 MW, however 8 MW turbines are being used in offshore locations. For perspective an average nuclear reactor is 1000 MW. Wind farms in the midwest vary in size but average around 200 turbines. A wind farm of this size could cover 50 square miles, but the actual footprint is minuscule as the land within the farm can still be used for forage/pasture.

Trump Pulls Out

It is now clear now that the current administration has withdrawn from the Paris Agreement for specious reasons. Trump will take us off the world stage, away from 195 countries who do recognize the risks of ignoring global warming, ocean acidification, and climate change.

Global warming as a concept is not new. Svante Arrhenius, a Swedish chemist and Nobel laureate wrote in 1896 on the risks of continued burning of fossil fuels and the resultant accumulation of Carbon Dioxide (CO2)in the atmosphere. [On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground] The concentration of CO2 in the atmosphere had been stable stable for hundreds of thousands of years – under 300 parts per million (PPM). In under 200 years we have raised the concentration to the current value of over 400 PPM, 150% of the value at the start of the industrial revolution.

Despite the relatively simple physical principals involved and despite the evidence from air and water temperatures, rising sea levels, and melting ice President Trump still thinks that global warming is a hoax. He seems fixated on the idea that developing sustainable energy supplies will drag our economy down. Is there evidence of such?

Very simply -No. Germany has installed more solar photovoltaic energy systems per capita than any other country, yet they are running a trade surplus with the United States. On a good day Denmark can produce 100 % of its energy from wind turbines and runs a considerable trade surplus with the United States. Ironically, much of their surplus involves selling wind turbine technology to us. We do have a small industry manufacturing wind turbine blades, but the company is Danish. China has leapt to the head of the pack for producing solar panels and we all know about their trade imbalance.

What do the captains of industry here think? Big fossil fuel producers such as Exxon-Mobil support the agreement. Even coal companies support the agreement. Walmart supports the agreement. Of course forward looking companies like Alphabet, the parent company of Google, Apple, Tesla support the agreement. Polls shows that the majority of Americans in every state, across the political spectrum support the agreement.

The agreement that we are walking away from is first and foremost voluntary. The agreement would in no way allow foreign influence of our laws or sovereignty. The agreement calls for international goals for reducing the rate of global warming by reducing the release of CO2 and other greenhouse gasses.

The US goal was a reduction of greenhouse gas emissions by 27 % of 2005 emissions by 2025. This is doable with a combination of energy efficiency, sustainable technologies such as wind and solar and switching from carbon intensive coal to natural gas. These changes to our economy are already underway and by participating in the agreement we show the world that we care about collective actions for all humanity, even for all life on this planet.

By not joining the agreement we turn away from 195 countries and join with Syria, torn by a violent civil war, and Nicaragua, who thinks the agreement doesn’t go far enough.

Booming Solar


Sustainable energy is currently the most rapidly expanding form of energy in the United States. The same is true here in Arkansas. Whereas we are not well set for wind as our neighbors are to the west, solar panels (PV) that generate electricity are effective, and getting cheaper by the day. Solar arrays now cost less than half of what they cost just 10 years ago.

The price is now so low as to be competitive with more conventional power sources such as coal and natural gas, and infinitely cleaner. Current solar capacity (as of 2015) is 20.1 megawatts (MW.) This is an unbelievable 640 % increase over all PV power installed up through 2014. The new power installed in 2015 is dominated by utility scale power, 15.4 MW. Commercial industries and businesses installed 0.24 MW and the residential sector 0.46 MW. This represents a 56 million dollar investment in clean energy and jobs.

Solar power has come of age, not just for people wanting a little power for an off-grid cabin in the woods, but residents tied to the grid, industries, and especially power companies. One real advantage of solar power is its scalability. If a power company needs to expand their energy supply a small amount, they can add a small solar field. If they need a lot of power, they install a bigger field. No alternative has this scalability. You just can’t build a (cost effective) small coal or nuclear plant. Not even natural gas fired turbines are as scalable.

The L’Oreal plant in North Little Rock will install several thousand PV panels, about 1 MW’s worth. In March 2016 a private-public consortium consisting of two Arkansas Electric Cooperative Corporations, and Aerojet Rocketdyne will install a 12 MW solar field near East Camden. The largest install this year will be an 81 MW solar farm to be installed by Entergy near Stuttgart.

Generally installs of home solar arrays are booming also. Most cost effective for the consumer is a grid-tied net metered array. This system allows the home owner to remain connected to the grid in addition to the solar panels. When the sun shines the panels provide energy to the house, but when the sun is not shining, the home can draw power from the grid just like any other home.

PV systems can be sized to provide all or any fraction of the power needed for the home. If a particular array actually produces more energy than can be consumed in a given month, the law allows the excess to be carried over to a month when energy is needed.

The consumers gain is however the power companies loss, and they don’t like it. They lose profits by not selling as much electricity and even worse net metering threatens the vertically integrated structure of the business. They are the power generators, the wholesalers, the distributors and the retailers, and they want to keep it that way. Other states, notably Arizona and Oklahoma, have instituted additional fees for home solar which will severely limit the development of truly distributed clean energy.

The Public Service Commission here in Arkansas is empowered by law to set rates and rate structures of electric utilities. Over the next year they will be conducting studies to determine if changes are needed (read additional costs to home solar users.) The utilities will be arguing that they have to claw back their profits to remain in business. Stay tuned.

Go Solar

The amount of solar energy available to the United States is overwhelming. With today’s Photovoltaic technology, 16 per cent efficient PV panels, the total energy needs of the country could be met using a land area of only 8,000 square miles. This is an incredibly small area compared to the 3.8 million square miles of total land area. All the solar panels we need to power the country could fit in a fraction of Elko County in Northeast Nevada.

Just imagine, miners don’t need to die underground to extract coal. Mountain tops don’t need to be blown off and pushed into valleys to get at a coal seam. We wouldn’t need to worry about whether fracking wastes pollute our ground water, or bust up the foundations of homes to access natural gas. We don’t need parking lots full of high level radioactive waste from nuclear power plants. Yes, you read that right. Our only plan for the storage of high level radioactive wastes, hot for tens of thousands of years, is to store the waste in concrete containers around the sites of nuclear plants.

The health of the public would be improved and incidentally the cost of healthcare lowered as we no longer would have have all the untoward things in the air that cause problems. Not burning any fossil fuels means less lung irritants such as fine particulates. Less heavy metals that cause nerve damage, less acid rain, less ozone, and the list goes on and on.

Rather than produce all the energy in a fraction of one county in Nevada, we could spread it out to the individual states. The US uses a total of about 4 trillion kWh per year. Closer to home, Arkansas uses about 50 billion kWh per year. To meet that need we would only use about 100 square miles, less than a tenth of the area of Arkansas County in the southeast part of the state. Or let’s make each county generate their share. For Pope County we need a scant 2 square miles out of 831. It’s easy to see that we have plenty of free, sustainable sunlight and the land foot print needed is not even an issue. We will also need to upgrade our transmission network, but still that’s doable. The real fly in the ointment is storage.

The aforementioned calculations of land area needed are for full power, 24/7 year around, assuming we have storage for when the sun doesn’t shine due to time of day, season or weather. This a problem but not an insurmountable one. Elon Musk, the manufacturer of the Tesla electric car, and Space X reusable rockets is building a huge battery factory in Sparks, Nevada. The battery factory will occupy a building covering an area equal to 95 football fields.

The factory will be powered exclusively by solar electric power, with energy to spare. The batteries built in this factory are lithium based and are intended for his fleet of electric cars, but it shows that really large scale production of all aspects of sustainable energy are not just something in the distant future but are close at hand.


Alternative Energy Alternatives

So you want to be green, or at least greener, when it comes to your electricity use. There are a welter of options available. Here in Arkansas we are not blessed with sufficient wind resources to make homeowner wind very cost effective, so going green means solar photovoltaic systems (solar PV) are the best game going. But with this restriction there are still several different approaches to decarbonize your electricity.

In remote areas without grid connections, the only reasonable green electricity is with a solar PV system and batteries. The batteries are necessary not only to tide you over for when the sun doesn’t shine but also to stabilize the power to your home or cabin. Imagine on an otherwise sunny day a solar array is providing nicely for the home, but a cloud passes over. This would temporarily reduce the current, possibly to the point of damaging electronics, Hence batteries are essential. Just how many batteries needed is a function of how long will the sun not keep up with demand. On occasion in this area we can go for a week or two without much sun due to rain and clouds. The point is that this is the most expensive option due to the costs associated with the batteries.

Much more practical are so called “grid tied” solar arrays which essentially use the electrical grid as a battery. If you buy electricity from Entergy, SWEPCO, or AVEC for example, and you add solar panels to your home, the power company is your battery. When the sun shines your meter will slow down or actually run backwards sending power to the grid. At night or on rainy or cloudy days power is drawn back from the grid. Because Arkansas is a net metering state, when producing you are paid the same price as when you buy. Depending on how many panels you have you can replace some or all of your electrical needs. Currently costs are such that the payback period is about half the rated lifetime of the panels. You will recoup your initial investment in about a dozen years, and the panels will continue to produce for at least that many years to come.

All homes don’t have access to the southern sky on their property due to shading from trees or the terrain. That said you can still participate via community solar farms. The first community solar farm has begun near Little Rock. A developer is constructing a solar farm tied to Entergy’s grid. Any Entergy customer can basically buy a piece of the solar production. The buyer has their own meter which is aggregated with their home meter, just as if the solar panels were on their roof. Entergy deducts any power costs produced by the solar panels from the power costs at the home. The cost for this approach is somewhat higher as because of the costs for site development and land acquisition.

Yet one more option exists to green up your electricity. The green power costs for the aforementioned approaches all require some significant start up costs. Another alternative is to buy “green tickets” or participate in the purchase of Renewable Energy Credits. There are companies that will for a nominal charge on top of your actual electric bill, buy green energy. The additional charge is used to buy power from green sources and send that electricity to the grid, which offsets electricity from fossil fueled sources. Basically you are subsidizing clean energy. You don’t own any equipment but your dollars go to green the environment.

Private Sector must be the Answer

In Al Gore’s award winning movie “An Inconvenient Truth” he used the old saw to depict a real problem with global warming. If you put a frog in hot water it will immediately jump out. Put a frog in cold water but very slowly warm it up and the frog will stay until it is too late and be boiled alive.

That is a nice analogy for the dilemma we face with with global warming. The process is slow. Another analogy would be to call it glacially slow, but glaciers are moving, and melting, at a fairly rapid pace these days. Humans and a number of animals evolved to react to rapidly occurring threats – the snap of a twig in the brush, the glint of light from an eye, and we are ready to fight or flee.

Global warming is a decades to centuries change that threatens us now, and many just don’t see the threat, a threat not to us individually, but to our future. Some are so insensitive to the risk that even if they believe it to be true, won’t react because it doesn’t matter to them personally. If the majority of us hold this opinion, we are doomed as a species.

Some governments are beginning to react with policies that favor carbon free energy strategies, but the steps are often small and can be more costly than simple business as usual burning of fossil fuels. Hey, it’s on face value cheaper and we know how it works.

On a more hopeful note is the fact that technology got us into this problem, but technology and the private sector, hold the potential to get us out. Obviously we need to stop burning fossil fuels, especially coal and oil. Natural Gas, essentially methane, is does not produce as much pollution as the others, but ultimately its use must be curtailed also.

There two ways to replace the fossil fuels, use less through efficiency and replace energy production with non-carbon sources such as wind, solar and geothermal. Of the three, wind is the most developed. We currently get about 4 % of our electric energy production from wind, entirely land based. The potential for off shore wind, especially on the east coast affords considerable potential but currently is more expensive to exploit than wind resources in the midwest. Currently the cost of wind generated power is as cheap as that from a modern coal fired plant. And the costs continue to decline, the opposite of the cost for producing power from coal.

Solar Photovoltaic systems (solar panels) are sprouting up everywhere, especially since the price has dropped by half in just the last few years. Not only are homeowners adding panels to their roofs but utility scale systems are being installed. Entergy recently announced that they intend to build a 500 acre solar farm near Stuttgart. For perspective, a square mile covers 640 acres.

Until the intermittent energy sources of wind and solar penetrate to about 30% of total production, no additional back up power is needed. Essentially there is enough existing reserve power to keep the lights on after dark when the wind isn’t blowing. Beyond that, battery backup will be needed. Development and deployment of utility scale battery production will surely follow the demand.

World Wide Wind

We will at some point cease to produce electrical energy by burning fossil fuels, either (sooner) because we realize the harmful effects of using the atmosphere as a toilet, or (later) because we simply use them all up. These fuels can be replaced with sustainable sources, principally wind and solar. Where are we now and where are we going?

In the United States we currently get 13 per cent of our electrical power from renewables. The majority of that from hydropower, followed by wind biomass and solar power as a distant fourth. There seems to be limited potential for growth in hydropower or biomass but the sky the limit for wind and solar, assuming that the issue of intermittency can be overcome.

Although we have no national policy for the country, president Obama has mandated that the federal government get 20% of its electrical energy from renewables by 2020. Various states have renewable portfolios that range from trivial to ambitious: The old south, a couple of coal states in the Appalachians, a few midwest to rocky mountain states have none. Hawaii has the most ambitious, with a target of 40% by 2030.

Internationally, it’s a mixed bag. Mountainous Costa Rica, with a population of about 5 million, gets from 90 to 100% of its electrical energy from renewables, mainly hydro and geothermal. Similarly Norway with twice the population of Costa Rica produces very close to 100% of their electric power from hydropower plants.

Because of availability of cheap electric power they have developed energy intensive industries such as the production high grade Silicon for solar cells. Interestingly a focus of World War II was on Norway. Germany invaded Norway to gain access to energy intensive production of heavy water for their experimental nuclear reactor program.

The real potential for expansion of renewable power is in the wind, especially in countries with lots of coastline. At one point last week, Denmark was producing 140 % of its electrical energy, exporting the excess to Sweden and Germany. Their current average wind produced electricity is approaching 40%, and they are still building out.

Germany is an interesting study. They have a vigorous low carbon energy transition plan (Energiewende.) Their target is an astounding 80% renewable by 2050! They are currently installing wind and solar PV faster than anybody on the planet. Currently they are around 27% with very little hydropower, twice the US average.

The biggest player of course is China. They are the current world leader in carbon emissions, having surpassed the US a few years ago. China’s air pollution problems are legendary. Smog from from eastern China can be tracked across the pacific to our west coast. They recognize they have a problem and are aggressively addressing it by moving away from fossil fuels and toward efficiency and renewables. In 2014 they installed three quarters of the new solar capacity on the planet.

tesla battery

Batteries for the Future – Now

A recent Op-Ed in the New York Times (about food) gave a hat tip to the Sierra Club and their Beyond Coal campaign – an effort to close all coal fired power plants by 2030. The point of the piece was the necessity of activism and organizing around a particular issue.

Since the inception of the program in 2010, no new coal plants have been built and 188 closed or planned to close in the near term. Currently just of under 40% of the electric generation capacity in the United States comes from burning coal, but the number is falling – replaced by natural gas plants and a mix of wind and solar.

As long as intermittent energy, wind and solar, constitute a small fraction of the total electric supply, grid operators can balance the load as needed by reducing power from the coal plants. But what about when the coal plants are gone? What do we do when the sun isn’t shining or the wind isn’t blowing?

There is no doubt that there is enough solar in the Southwestern US or wind the Midwest to power the nation, but storage and transmission is a controlling factor to the use of these clean sources of energy. Tea party types are resisting transmission lines on the basis of property rights and governments in conservative states are making small scale renewable energy less attractive to protect their power companies’ turf.

When one thinks of energy storage, explicitly electrical energy, batteries are it. Enter Elon Musk, billionaire entrepreneur and builder of the Tesla Electric car. More important than the electric car are the batteries that power them, at least that is what Mr. Musk thinks. He has recently gone into the battery market, not only for his cars, but for stationary applications. He introduced a 10 kWh battery that can be used for a myriad of applications.

For a home owner this means “behind the meter” storage. Obviously off the grid folks rely on batteries but even grid-tied homes can utilize storage for weathering storms when the grid goes down. Folks with grid-tied renewable energy systems can utilize storage. Some power companies have time of use metering, that is the cost of power varies as to when it is used. If a home owner has a storage capacity, S/he can chose to sell power back to the grid when the price is higher. Even without a renewable energy supply, home owners with storage can charge batteries during the night when rates are lower, then sell power back to the grid during the day, making a profit in the exchange.

Utility scale storage can be beneficial right now. Battery storage can be added incrementally to defer transmission and distribution line upgrades as demand grows. Batteries can be used to back up temporary shortages due to short term power plant outages. Not to get too far down in the weeds on these issues, suffice it to say the Batteries will play a huge part in the future of clean energy supplies.

This something we should all strive for. We will get away from burning stuff for power, and batteries will make this more practical.


A Positive Potpourri

So much news about global warming and climate change is negative. The planet’s hotter, the weather weirder, and the future dimmer. Whereas over half of Americans believe in global warming, less than half care. But there is some hope for the future out there.

Little is coming out of congress but the state of California is leading the way to a sustainable future. The land of “fruits and nuts,” the land where the leader is referred to as “Governor Moonbeam,” will be breaking ground for a new high speed rail to run from San Jose to Los Angeles. The nation’s largest infrastructure project will cost billions but take scads of cars off the highways and planes from the sky. It will produce jobs that can’t be sent overseas, and most importantly reduce the carbon footprint for the people of California.

And speaking of a carbon footprint, Governor Jerry Brown has set an ambitious goal of 50 % of the energy to come from clean sustainable sources such as wind, solar and geothermal by 2030. Nowhere else in the country is there such an ambitious standard.

The Journal of Environmental Studies and Sciences show that the cost of onshore wind and solar PV are cheaper than coal for generating electricity, when the cost of climate forcing is factored into the use of fossil fuels, either gas or coal. The cost of solar panels alone has dropped by 50% between 2008 and 2009. Although Solar PV generated electricity only accounts of a scant 0.7 % of installed capacity, it recently has become the the most rapidly installed new generation in the country.

The oil and gas boom due to technological advances like shale fracking have accounted for a 10% reduction in oil imports (equivalent). That’s good but automotive efficiency due to gas mileage standards coupled with increase utilization of mass transit has resulted in nearly twice the savings, some 18% reduction. Reductions due to efficiency are far too often overlooked when considering reducing our reliance on fossil fuels.

An important aspect of sustainable energy is the fact that it creates jobs, more than any of the fossil fuel industries. The US Bureau of Labor Statistics estimates that there are about 80,000 jobs in the coal mining industry, but over a 142,00 jobs in solar industries.

Several HVDC transmissions are moving through regulatory approval, including the Plains and Clean Line which will pass through Pope county. When approved and constructed, they will allow the utilization of much otherwise stranded electric generating capacity from abundant midwestern wind.

Also here in Arkansas, a 12 megawatt (MW) solar photovoltaic installation will be built on a one hundred acre site in an industrial park in East Camden. Arkansas Electric Cooperative Corporation (AECC) will sell power to their members across Arkansas. AECC has also agreed to purchase an additional 150 MW for a total of 201 MW of wind power from producers in Oklahoma. An 80 MW wind turbine farm has been proposed for a site near Springdale. It will use a novel shrouded turbine design which is claimed to completely eliminate bird and bat mortality.

Energy Costs and Financing

It is difficult to compare the costs for energy from various sources, but it is an important issue. In Arkansas we are blessed with (or cursed by, depending on your point of view) relatively low electrical energy costs. We pay about eight to nine cents per kilowatt- hour (kWh) which is about three cents below the national average of twelve cents. In some locations and at some times of the day the costs can go over 25 cents per kWh. These costs do not include externalities such as damage to health and the environment, risks associated with global warming, political instability and direct subsidies to insure risky technologies.

It has been estimated that the inclusion of these costs could raise a monthly electric bill by two to five times. An average Arkansan’s electric bill would be closer to five hundred dollars rather than slightly over one hundred dollars per month.

Clean renewable energy from for example photo voltaic systems (PV, solar electric panels) can be prohibitively expensive when you compare the costs without consideration of the external costs of traditional electricity production. It would seem only fair then to subsidize PV systems and that is happening to a limited degree.

5.4 kW solar array

5.4 kW solar array

The federal government provides a thirty percent tax credit for residential and small commercial systems which makes these systems more competitive with traditional energy sources with their hidden subsidies. Recently the state of Arkansas through the Arkansas energy office has begun an additional subsidy based on energy produced by renewable energy systems. For program details see: http://arkansasenergy.org/.

The current program from the state provides for on-bill financing for qualified energy efficiency improvements that consumers can install on their premises: energy efficiency measures, distributed generation (e.g., solar photovoltaic, combined heat and power), and demand response (DR) technologies.

shade trees same energy

shade trees same energy

Consumers typically have extensive experience making utility bill payments, it is already a routine part of their lives. It is also conceptually attractive to make an investment where the energy savings that result are reflected in the same bill as the payments on the loan that funded the investment. This method of financing is particularly attractive for projects which have long pay back times. If the original owner sells the property, the financing remains with the improved property.

Low-E glass saves energy

Low-E glass saves energy

Because we have relatively low electric costs here in Arkansas, the payback for subsidized systems can be on the order of a couple of decades for large projects such as PV systems. In locations with much higher electric rates, say 25 cents per kWh, the payback would be much sooner.

The question then becomes, do you want to continue wars, and general global political instability because of our reliance on oil imports? Do you want to continue to support scraping the tops off of mountains to get at “cheap coal”. Do you want to continue to contribute to the degradation of the environment from oil spills? Do you want to contribute to the degradation of health through air pollution? To the deaths of miners and drillers? Global warming and ocean acidification?

You can walk away from all that now, but sustainable clean energy supplies are a future you can make happen now.