When we wrote our story, Small vs Large Solar, we thought we were alone in wondering why mammoth solar plants that cover thousands of acres of desert habitat were being emphasized over distributed solar that would cover the roofs of millions of buildings in the US.
But others are questioning this approach too. A Colorado group, Solar Done Right, has issued a report, "Wrong From the Start," which questions the Obama administration’s public lands solar policy and explores distributed energy alternatives as a much better way to mainstream renewable energy.
The Bureau of Land Management’s solar policy would open hundreds of thousands of acres of public lands to industrial scale solar plants.
Solar Done Right asks federal agencies to include in its analysis consideration of smaller projects such as photovoltaic solar arrays on the rooftops of homes and businesses, over parking lots, on already-disturbed lands and near transmission substations.
By doing this, the need for expensive new transmission lines would be eliminated and solar could blanket the US much more quickly. It would also put the average person and business in the driver’s seat, making them self-sufficient power producers as Germany has done.
Despite the crucial importance of lowering carbon emissions, no scientific studies have examined the claim that these projects reduce net greenhouse emissions when construction, transmission, and disruption of carbon-sequestering ecosystems are taken into account.
Solar Done Right says: Habitat destruction threatens the diversity of life on this planet. Renewable energy strategies that damage habitat only make the problem worse. Distributed generation such as rooftop solar is the faster, cheaper, cleaner and more effective way of meeting our energy needs in the next century.
With 253 million acres in BLM-managed lands alone, it may seem that the public lands, and their potential for use, are endless. Yet much of this area is already damaged or fragmented by mining, urban encroachment, oil and gas operations, livestock grazing, motorized recreation, and other uses. Large, contiguous areas that retain their ecological integrity are increasingly rare: these are some of the areas most acutely threatened by large-scale uses such as industrial solar.
There is a widely held misconception that point-of-use distributed rooftop solar photovoltaic (PV) is too expensive, too slow to implement, and inadequate to meet our renewable energy needs, and that remote utility-scale solar power plants should be the centerpiece of our nation’s solar energy policy.
The California Energy Commission has said in assessments of various utility-scale solar power projects that, although such projects will cause substantial and unmitigable harm to the environment, regulations normally restricting these impacts should be overridden in light of the urgency of reducing greenhouse gases and meeting California’s Renewable Portfolio Standard. Yet distributed PV can achieve the same objective without the environmental harm and at lower cost.
Our deserts are irrigated by water that fell thousands of years ago, covered in vegetative assemblages that have been developing for longer than recorded human history, and some of the individual plants in them are older than the oldest bristlecone pines. Once altered, those plant communities may never return to their original state even under optimal conditions. If the desert’s aquifers and vegetative communities are forever changed, the animal wildlife that has evolved dependence on local springs, plant habitat and edible vegetation will suffer. Given the permanent damage that would result from industrial energy development in desert wildlands, it’s time we stopped calling such development "renewable energy."
Industrial-scale solar power generation is economically feasible only because recent policy has brought massive taxpayer-funded subsidies to the table. Ironically, many of the names behind Big Solar that are taking advantage of this policy are familiar from the realms of of Big Oil (BP and Chevron) and big bailouts (Goldman Sachs and Morgan Stanley).
Michael Brune, executive director of the Sierra Club has called for large scale solar development in places where it will do the least harm – on disturbed land, such as abandoned agricultural lands and defunct mines – and on rooftops and parking lots.
Here’s the report:
Big solar is easier because you can do one project instead of hundreds. You are right about the advantages of distributed solar. In addition to the advantages that you mention, when small solar is deployed in a hybrid microgrid with some combination of storage. electric vehicles, other distributed generation and load management, it can provide bullet-proof reliability. These technologies have just begun to mature. They will take off when large numbers of people understand how all the pieces fit together. That is why the National Renewable Energy Laboratory developed the Hybrid Optimization model http://www.homerenergy.com .
Parking lots in the U.S. are vast and are perfect places for solar carports and for solar-powered EV charging stations, the latter of which would help solar replace not only coal, but oil too!
The utilities themselves admit that 50% of the power is lost in transmission. But putting solar on everyone’s rooftop means less $$$ for them. Hmmm. I wonder why the utilities prefer “big solar” which destroys our deserts with these ugly plants, and destroys all our mountain passes with transmission towers.
INDIA HAS AN OPTION TO USE SOLAR ENERGY MORE PROFITABLLY
P. S. Deodhar
Maharashtra Government?s decision to install 150MW PV Solar Plant in Dhule is one amongst the several such multi-megawatt PV Solar power plants being planned or installed everywhere in the country. For several valid reasons, a lot of us are convinced that installing such large centralized plants to utilize omnipresent solar power is unnecessary and wasteful investment besides being technologically inappropriate. Such plants will also not give any practical relief to the consumers who today suffer from long blackouts and extreme voltage swings. It may be glamorous and good ?breaking news? but, does not offer any real benefit.
US based World Energy Report of December 2010 recommends distributed solar power plants of 50kW to 500kW as ?practical?. They found that it is better to build smaller and more efficient solar power plants to serve demands of local communities using free solar energy. One therefore wonders why our energy planners prefer mammoth solar plants that cover hundreds of acres of land and not focus on using the most important merit of the solar energy; being available everywhere unlike a waterfall for hydropower or coal mines for thermal plants?
No ?location? Handicap:
Solar energy is omnipresent so it can be harvested for power at any place. However in case of conventional power plants, hydro or thermal, they have to be where energy source is. This made it necessary for us to transport it at great cost to places where it is needed. Against this, Solar Power Plants generate power wherever it is needed; on the mountain tops or deep in no man?s land. Solar is therefore ideal for distributed power generation saving line losses in transporting power and hazardous high voltage transmission. Such plants will supplement the grid at local level during critical day time when power loss affects the productivity of local industries and offices.
No ?Scale Advantage?:
Many may not know that the cost per watt of solar power is the same for a 10kW plant or 150MW plant. In fact, the land cost and other soft costs make big plants much more expensive. Contrary to hydro or thermal power plants, there is no ?scale advantage? in going for large PV Solar plants. In reality all multi-megawatt plants are basically clusters of several 500kW plants since, Solar Inverter capacities are limited to about 500kW and no more. As you read though this article you will realize that it would be cheaper and more advantageous to build three hundred 500kW plants in as many districts than building one 150MW plant in Dhule. More importantly you will realize that the distributed power option will immediately improve the power quality to the people during the working day and consequently improve the productivity tremendously. Unfortunately, you will realize, 150MW plant feeding power at 66kV or 132kV won?t!
Avoidable Feed-in and Feed-out losses:
The biggest problem with the Multi-megawatt PV solar plant is 12 to 15% loss of expensive power in a series of power transformers. PV solar plants generate its power at 400V three phase. In multi-megawatt plants, this power is first boosted to 66kV or more with power transformers for feeding into the grid. Power utility then needs another string of transformers to step down this 66kV solar power back to 400V at your local substation since most consumers use the power at 400V. In addition, there is a further transmission loss of 5 to 7% in the power grid. Why suffer absolutely unnecessary 20% loss of rather expensive solar power!
Use of huge land areas
One limitation of PV solar power is the area covered per kilowatt. Currently one would need about three acres of land per megawatt of solar power! 150MW would need few hundred acres of land. What kind of land do we have and what price the land is made available? Land can be always used more profitably that covering it with solar panels. Small plants of 500kW or 1MW are being in the US and Europe on unused roof tops and terraces. Every town has enough terrace space in India to put up 100 to 500kW solar plants. Gujarat Government is already promoting this officially. Why increase the cost of solar power due to this? One save money by reducing support rate paid if unused terraces are put to profitable use. UK and German Governments pay far less rates to buy energy from power plants above 50KW. They buy power at much higher rate from small producers of solar energy. Find their logic.
Power Grid Behaviour
Finally the last problem is we seem to be ignoring the way power flows in the power grid and its impedance network analysis. Huge amount power is always circulating at 66kV level in the grid. Injecting even 150MW power is just a tiny faction. So this small addition brings no great relief to customer?s problems of blackouts and wide fluctuations at fag end of the grid. Voltage swings occur because of the high impedance of the grid at its fag end. Line drops are the cause. Feeding solar power locally at 400V will immediately reduce the network impedance and deliver stable clean power to local communities. In fact when solar power is injected at 66kv as much as 25% of the good quality power that solar plant produces gets lost in the grid; if at all benefitting the big consumers who draw power at high tension.
Many Benefits of Distributed Solar Power Feed
Governments indeed have another meaningful and technically sound alternative to use the PV solar power. It is the most effective and profitable way to redress our power problems at the consumer end. This is the way many experts now believe is the right way.
Local PV under 300kW Solar Power Plants
? We need to encourage, say, a 300kW solar plant installed on currently unused terraces and roofs to install solar panels in the vicinity of a substation. This plant will inject its 400V three phase output directly into local end of the grid at a substation.
? Injecting high quality solar power in this way will immediately improve the quality of local power during the day time avoiding blackouts and voltage fluctuations. Loss of power during the day time is the most common problem for the farmers and industrial consumers.
? This will also eliminate huge losses of 15 to 20% in stepping up and stepping down power from mammoth plants.
? In fact, it is the daytime when the substation transformers tend to fail due to overheat. Injecting solar power will make these transformers run cool; extending their life.
Encourage SME owned Local PV Power Plants
The state can benefit the most by creating a new opportunity for SME investment in Solar Power Generation.
? Promote local enterprise to get into power generation. This will create thousands of new SME power companies.
? They will generate local employment besides generating solar power. SMEs will also ensure that the plants are maintained with great care.
Helping Economic Growth with improved productivity
Finally the most important of all is the productivity gain when community gets clean stable power during working hours for at least 300 days in a year. Besides avoiding the industrial productivity losses, good power quality will help people avoiding premature failure of electrical equipments in their homes, offices and workshops.
It will also put to good use of currently unused roofs and terraces of private and government buildings and backyards in the nearby localities…
Why Solar Energy will prevail over Nuclear and other Energy Sources?
Let us understand that clean and free solar energy is indeed a god?s gift to mankind. Sun delivers more energy to us in one hour (4200 GWH) than the whole world consumes in one year; 50% of it is heat, 45% in visible light and about 4% in ultra-violet. Current PV solar technology that is widely being used in the world has great merits and is the most appropriate alternative to any other electrical energy option. In fact, the Sun produces its own energy by the nuclear process of Fusion. But all the hazards connected with the nuclear energy are taken care of on the Sun and ‘clean energy’, free from all conceivable hazards and risks, is showered on us free of cost. Many of us believe that solar energy will ultimately prevail over everything else. Time is now for India to focus on energy research in this area as well as green energy efficient appliances and light sources like LEDs.
Since the energy input is free of cost, cost of PV solar energy is basically capital appropriation cost. Any accountant will tell you that the cost of well managed PV Solar power is currently less than Rs.9/-