We have discussed the basics of solar panel technology, given you some idea of their costs, and introduced the topic of efficiency. Today’s column will examine the environmental impacts and efficiencies of solar power in more depth.
We all want to do the right thing: Cut down on emissions; reduce our carbon footprint; take pressure off of power utilities to construct more generating capacity.
Silicon production requires large amounts of energy, which, in China comes from coal-burning thermal plants. A study recently released by Northwestern University found that the carbon footprint of a solar panel from China is twice that of one from Europe.
Solar panels use rare earth minerals, mostly from China, in their manufacture.
Mining and processing these rare earths generate a range of hazardous byproducts. In that part of China where rare earths are mined, soil and water are saturated with toxic substances, making farming impossible.
In the finished panels, thin-film photovoltaics are made from a number of heavy metal combinations:
When sealed inside glass panels, these compounds are harmless.
However, like anything else left out in the weather, solar panels suffer gradual degradation from ultraviolet light; rain, snow, dirt, temperature fluctuations, hail and wind. If leaked from the panel, the thin-film metallic components can inflict serious environmental damage.
Panels must be disposed of with extreme care in order to keep these carcinogenic substances from leeching into soil and groundwater.
Deep-cycle lead-acid batteries, store power produced by solar arrays to ensure a constant supply of electricity. These batteries contain lead and sulfuric acid, which are both highly toxic. Most of the material in spent batteries is recoverable if the batteries are properly recycled, as long as consumers make the effort.
Right now, solar panel recycling suffers from a chicken-or-egg problem: There aren’t enough places to recycle old solar panels, and there aren’t enough spent solar panels to make recycling them economically attractive.
You know how these things go. The used solar panels will be quietly stockpiled and left to decay in someone else’s back yard. Not what citizens of good conscience intend or want.
Arguably, the value of intermittent electricity is the value of the fuel the intermittent electricity replaces. But, what is an appropriate valuation when looking at hydro-power? In BC’s case, the value of replaced hydro-power is represented by a tradeoff of a wholesale kWh from BC Hydro versus a solar kWh.
For BC Hydro, intermittent electricity does not reduce any costs. The power company still needs to provide backup power around the clock to its customers with solar panels.
The variability in production still requires the company to operate much the same capacity as in the past, and it needs the same staffing for each of the units, even though some of them might be operating for a smaller percentage of time.
The following chart demonstrates California’s experience as solar has become a more important factor in its power supply.
The tan body of the duck represents unused hydro, nuclear and thermal generation capacity.
In 2013, power demand from the grid stayed relatively flat through the day, ramping up during the evening hours when dinner was being prepared, television viewing increased, people turned on their air conditioning, etc., not falling off until late evening, bedtime.
In comparison, the 2015 curve, reflecting increased reliance on alternative energy, shows power usage from conventional sources declining through the middle of the day. And, by 2020, the duck is expected to be much fatter.
The real solution to intermittent power generation is bigger and more flexible grids. The bigger the geographical area a power network covers, the greater the chance that electricity generated in one place can be matched with demand elsewhere.
Further, funding for the additional electrical transmission lines and maintenance will likely be problematical. Neither the Hydro nor the BC Government has sufficient revenue to fund these requirements.
Credit for power fed into the grid needs to be carefully thought through. It is politically expedient for the solar user to be given credit for more than the wholesale price of electricity for the electricity generated by solar panels. However, a high level of reimbursement leaves a revenue shortfall for BC Hydro, producing electricity and maintaining the grid;; expanding the distribution system is yet another consideration.
So, we are asking for BC Hydro to maintain its full capability; in fact, to expand its services to better integrate solar generation into the grid, all while receiving less revenue.
There is a certain fixed cost to the existence of the grid. When all electricity is delivered over the grid then the grid can cover its fixed costs.
However, there are those whose connection to the grid is not supplying all of their electricity. When we take into account that they are not being charged for the costs of taking their newly generated solar power away from their houses either, they are only contributing to overhead.
Net metering provides an unfair advantage to solar consumers, who don’t pay to maintain the power grid although they draw from it and rely on it for backup on cloudy days. The more people who produce their own electricity through solar, the fewer are left being billed for the transmission lines, substations and computer systems that make up the grid. One could argue, with some conviction, that those who choose not to install solar power are subsidizing the solar power households.
The cost of solar power is not just about the systems that households and businesses install. On cloudy days and at night, they need power from elsewhere: either from storage, or from the grid. But who is to pay for it? Backup generation, and the grid infrastructure across which it flows, become increasingly uneconomic as consumers generate more of their own power, paying less to the power company.
The problem is that a home’s demand for electricity does not necessarily occur at the same time that the sun is out. Homes, of course, need power at night and on cloudy days. Remember the duck chart, above. Solar systems feed power back into the grid, which allows homes to draw from the grid when the sun isn’t shining, but that still entails reliance on conventional power sources when the weather is overcast or at night.
Consumers cannot afford high-priced electricity and will not allow their standards of living to be compromised. To deal with this reality, Victoria will be pressured to change its overall electricity mix to include more low-cost energy sources (more hydro? nuclear?) in the electricity mix to keep the overall price of power affordable, which is at least part of the problem behind Germany’s difficulties with solar.
Next Week: The German Experience
With over a third of the world’s nameplate solar capacity, Germany is often presented as an example of success. The German story is far more complex; we will do our best to give you a balanced view.
“Europe’s Green Energy Industry Faces Collapse As Subsidies Are Cut” – Michael Bastasch – http://dailycaller.com/2014/06/24/europes-green-energy-industry-faces-collapse-as-subsidies-are-cut/
“The darker side of solar power” – The Globe and Mail – Konrad YakabuskiI – http://www.theglobeandmail.com/globe-debate/the-darker-side-of-solar-power/article24649804/
“The Dirty Side of a “Green” Industry” – Yingling Liu – http://www.worldwatch.org/node/5650
“The Hole in the Rooftop Solar-Panel Craze” – The Wall Street Journal – Brian H. Potts – http://www.wsj.com/articles/the-hole-in-the-rooftop-solar-panel-craze-1431899563
The uncomfortable choice with solar power and raw material sourcing – Chris Berry – http://www.pv-tech.org/guest_blog/the_uncomfortable_choice_with_solar_power_and_raw_material_sourcing
Crystal clear? – Perovskites may give silicon solar cells a run for their money – http://www.economist.com/news/science-and-technology/21651166-perovskites-may-give-silicon-solar-cells-run-their-money-crystal-clear