| Most electric utilities in the Midwest USA burn coal to generate most of the electricity they sell. This results in huge quantities of air and water pollution, especially compared with electric utilities less reliant on coal. Stated succinctly, a kilowatt-hour (kWh) from a typical Midwest USA utility is much more associated with pollution than the average kWh sold in the USA. Global warming-related CO2, acid-rain-causing SO2, smog-generating NOx, nerve-toxic mercury and lung-harming particulates are the biggest emissions from coal plants. Even if scrubbers and other devices or techniques are used to clean up coal and generator emissions, CO2 emissions are still huge compared with almost any other fuel, because CO2 is the most difficult emission to reduce. Yet many electricity consumers, often those in all-electric homes, often don't even understand this associated pollution, simply because they don't experience, see or generate it directly. I've developed a term to describe and quantify the pollution which is not generated onsite where a consumer is, but nonetheless is associated with energy that a consumer uses: "pollution demand". |
| My dad once told me he thought one of the best advancements of his generation was getting coal-fired furnaces out of the basements of most homes, as was the case where he lived as a child. He told how clothes dried on an outdoor clothesline often had soot on them when brought inside after drying. So he thought gas furnaces were a wonderful invention. |
| I recall telling him one day that despite his contention, we now burn more coal than ever, and that coal pollution was a much worse problem than it ever was in the past. I also said that nowdays it is typically hidden from most of the people who are using it in the cities and suburbs. I argued then, as I still do today, that this out-of-sight pollution reduces incentives for the most responsible consumers to confront their coal pollution. Not only that, but the unfortunate people who live or work in the areas nearest those coal plants end up suffering with the filth and unhealthiness that the majority of the electricity consumers can't see. This same issue relates to coal miners, who typically don't live in the cities and suburbs where the most electricity consumption occurs. Their health issues and environmental nightmares like mountain-top removal to retrieve coal more cheaply are not where most electricity consumers can see it. This renders these problems as abstracts to a typical electricity consumer in the Midwest USA. It's hard to expect someone to be disturbed or motivated by abstraction. |
| I believe that if we mined and burned the coal in our backyards to generate our own electricity, we would soon recall and understand how filthy coal is. If we were coal miners or if we lived next to a coal mine or power plant, we would yearn for the alternatives. I believe most coal-fired electricity consumers tolerate coal simply because most of them do not personally confront it, and because coal-fired electricity is so cheap. Indeed, in most of the Midwest USA, coal-fired electricity prices decline the more is purchased per month! This leads to wastefulness and extravagance about how it is used. It also leads consumers to ignore the alternatives, which just about all cost more. About the only alternative which doesn't cost more is conservation, by not using as much or being more efficient. |
| But is coal power really cheap? Energy expert Amory Lovins once said that the cost to build large utility-scale power plants for new homes just about equals the cost of the homes themselves. This cost is hidden from new homebuyers and distributed into all utility customers' rates. Because of this, typical new homebuyers do not pursue energy efficiency and management concepts in their new homes at a time when it is cheapest and easiest to achieve the greatest efficiency gains. This leaves our society with huge growing inventories of energy-guzzling homes and buildings. If new demands for electricity were charged one-time-only fees per supplied new amp of capacity, new demand for utility-supplied electricity could be restrained at the same time that older homes and buildings would be freed some from the utility costs of new generation. This would at least acknowledge that new structures and equipment installations can often take better advantage of efficiency and alternatives than older structures with older equipment. |
| And what about the health costs of burning so much coal? Right now these are inside health insurance, taxes, business and personal medical costs, not in the energy price where its cost would be more visible and instructive to consumers. I wish there was some easy political or legal way to move health and environmental costs from coal into the direct cost of coal-fired electricity. But politics and law are beyond the scope of this writing, and my hope is probably also beyond political possibility in our lifetimes. Frustrations like this lead many of us to consider solutions which we can implement ourselves or at least monitor locally. Most of the best and least-cost solutions involve reducing demand for coal through efficiency and conservation. Solar electricity is another solution. Ideally, if enough efficiency, conservation and solar were implemented by enough consumers, we'd be able to shutdown at least some coal plants because they'd not be needed. But this is idealism, not likely. The demand for electricity, especially cheap electricity, is fierce. So this leads people like me at least to reduce our own responsibility or "pollution demand" as much as we can. |
| Electricity from the sun, called photovoltaics or PV) is one way to generate electricity which is simple enough to be available to residential and light-commercial consumers. PVs do not cause respiratory disease or acid rain or threaten global warming. However, PV generators are at least twice or three times as expensive as coal-fired generators. Because of the high cost of PVs, users who want to rely on them must reduce their demand for electricity to a level they can afford to produce. |
| There are some simple rules of thumb about most flat-plate PV collectors. |
| 1. Up to 8 - 12 watts per hour can be expected per each square foot illuminated by and directly facing full sun. |
| 2. Good sunlight is not available every hour or every day, so storage batteries are needed if continuous solar power is the goal. Otherwise, some other real-time backup generation is required. |
| 3. The cost of PVs are down to five to six dollars per watt, but complete (installed) systems average $10 - $20 per watt. |
| Since the Midwest USA has more clouds in winter than summer, a user relying on PVs must design around the seasonally varying average output from PVs. If the consumer's electricity consumption varies seasonally, with greater demand during summer, then that matches better the PV likely output. For instance, one square-foot of PV, tilted up at 45 degrees and aimed perfected south might generate around 0.5 kWhs per month around the winter solstice, about 1.2 kWhs per month around the summer solstice, somewhere around 1.0 in spring and fall. |
| The 2.4 to 1 ratio of summer to winter PV electricity generation and the high cost of PV systems might encourage most Midwest USA PV users to consider reducing their demand for electricity, especially in winter, or else have another backup generation source for seasonal use. Some off-the-grid PV users in the Midwest USA add a wind generator to their renewable power system, because our cloudier winters have typically twice or more wind than our summers. This makes wind power a good match-up with PV in the Midwest because their power supply outputs complement each other so well. |
| Although PV prices are steadily dropping, they will probably never be "coal-cheap" in most of our lifetimes. And there is yet another cost for the do-it-yourselfer. Before just deciding to jump off-the-grid, be sure you are ready for the job of being your own utility! If you are off-the-grid and your power goes off, most PV-users can't just call the utility or even the local electrician to solve the problem. Since many off-the-grid installations are in remote areas, the best solution is to learn to at least troubleshoot your own system. Many problems are simple enough that an informed user can diagnose and repair the problem, even if a new part is needed now and then. At the time of this writing, off-the-gridders who live close to full-time system dealers and solar technicians are lucky and comparably few. |
| Short of going completely off-grid with PVs, consider moving individual, intermittent or smaller tasks to PV. A larger example includes a vacation cottage which is used only occasionally, especially less often during winter. Another example is an in-home office where plug and switch loads can be moved to PVs (as I did for my own office in 2001). Simply because these have lower and less intense energy demands typically than entire houses or buildings, the task and expenses are easier and cheaper. |
| If you're wanting to become more acquainted with PVs, but want an even smaller project, consider converting small household tasks and devices to PV, like portable stereos, beard trimmers and anything else which can use or has rechargeable batteries. You might be surprised just how many of these opportunities you have! I was! I discovered I was using almost 50 small "D", "AA", "AAA" and 9-volt batteries for various household and business devices. I've bought rechargeable batteries for each of these and charge all my batteries using PV. Since the cost of electricity is usually highest when gotten from small batteries, these are perfect candidates for converting to PV. Just about anything that has a rechargeable battery can be charged by PV. |
| Grid-intertied PV systems: |
| The current rising interest and trend toward grid-intertied PV systems is very different in scope, cost and accomplishment from off-the-grid systems. First, this interest is typically coming from city and suburb dwellers who already have access to cheap utility power, but who want more environmentally clean power than coal or nuclear. Grid-intertied systems are simply connected to and synchronized with the utility power grid. When there is no onsite need for power, it flows back into the utility grid. There are complicated, regionally-specific issues surrounding how or whether the utilities pay the small power producer for this PV power, compared with consumer electric rates paid during other times, since the PV power is not always produced when the utility even needs to buy more power. Some of these issues are logical, others political, but they are also changing rapidly as public interest in solar increases. |
| Regardless of the legal issues, PVs only produce power when there is sun, so grid-intertied PV systems (which typically have no batteries for storage) end up relying on conventional utility electricity generation for their backup electricity. This means that when the utility grid goes down during a storm or on a cold, stormy winter night, so does the grid-tied consumer without batteries. It also means that if it's cloudy and a grid-tied consumer's PVs are not generating, the user is again relying on the grid for polluting power, unless he or she can shut down electrical demand except where there is ample sun. This makes it difficult sometimes to quantify the environmental benefit of grid-tied solar electric systems without batteries, especially in cloudy regions like the Midwest USA. |
| Finally, grid-intertied systems do not typically offer incentives and encouragement for minimal power dependence, storage, back-up and sustainable use as do off-the-grid systems. The self reliance and super-efficiency achieved and treasured by the typical off-the-gridder is not typically achieved by grid-intertied consumers, since there is no realtime physical penalty for matching use with PV generation. Indeed, in my own experience converting and running my office on PVs, this matching effort encouraged me to reduce my office energy consumption by around 80%, all done more cheaply than the cost of installing more PVs. So if one's goal is to become the greenest power consumer, grid-tied or not, remember that becoming more green in the coal-dominated Midwest USA typically means minimizing demand for coal, not using the most solar. And PV is not the only kind of solar, just the most expensive kind. If you're interested in other kinds of solar, check out my "Types of Solar" page. |
| As we move toward the future, there will undoubtedly be more use of solar, including solar electricity. Even if you can't afford to go 100% solar, it's a good idea to learn more about it. Now's the time to at least get educated about it. |
| E-mail: johnfrobbins@insightbb.com |