Solar Electic Power

Thanks to my opponent for continuing with this debate. I apologize for calling my opponent "Con" in the last round. He is "Pro" of course. I tend to screw that up.Our debate has turned from the nice clean topic of how many solar panels are needed to the dirty business of figuring capital costs, maintenance, depreciation, insurance, and taxes. For a coal fired power plant, only about a third of the cost is coal, Two thirds is "other." It is characteristic of discussions of green energy that all those other costs are quietly ignored. They are real and cannot be wished away.In the last round, Pro increased the equipment cost to $90,283 to correct for panel deterioration. He agreed with the costs of insurance and taxes. I'll use those numbers. We agreed to use an increase of grid power cost at 4.6% per year; that includes an inflation component.Batteries are a painPro referenced a page that lists deep cycle batteries as one type available. The page points out "In situations where multiple batteries are connected in series, parallel or series/parallel, replacement batteries should be the same size, type and manufacturer (if possible). Age and usage level should be the same as the companion batteries. Do not put a new battery in a pack which is more than 6 months old or has more than 75 cycles. Either replace with all new or use a good used battery." A single bad battery can trigger replacing them all. At minimum an extra cost to keep spare capacity and having a system in which batteries can be removed.The referenced page says "Lifespan can also be seriously reduced at higher temperatures - most manufacturers state this as a 50% loss in life for every 15 degrees F over a 77 degree cell temperature." Also, "The standard rating for batteries is at room temperature - 25 degrees C (about 77 F). At approximately -22 degrees F (-27 C), battery AH capacity drops to 50%. At freezing, capacity is reduced by 20%." The batteries are supposed to be sealed, but they produce hydrogen if they are overcharged. There is an elaborate safety protocol for battery charging. http://www.wisconsin.edu... All this means we have to have a well designed rack structure with ventilation for the batteries, and it should be in a space protected from temperature extremes. Doing that will add to the cost.MaintenancePro argued that maintenance costs should be a little less because a person could hire a neighborhood kid to do the roof work and electrical maintenance. I think that should either be rejected or the insurance premium for liability on an unlicensed kid doing roof and electrical work be added to the maintenance cost. I don't think that insurance for that is available, so I'm sticking with my estimate. Where I live, a visit from a licensed lumber costs $125, even if he does nothing other than arrive. My $50 estimate is conservative.Selling back electricityI think the ground rule for this debate was a system not connected to the power grid. That's the only way to make a clean comparison without figuring all the costs of randomly accepting power into the grid system. Pro's claim to sell power into the grid is a violation of the ground rule and should not be considered. However, if that route is taken, a much more elaborate control system is required to interface the solar power to the grid. Also, much of that work cannot be practically accomplished by a homeowner, because the electrical code requirements are so extensive. There is a substantial cost for building and maintaining the electrical grid system. Pro argues that the grid is already there, so those costs should not count. That's wrong on principle, When you use something you should pay the proportionate costs. A rental car company has all the cars just sitting there, but when you want to use one you must pay the entire burden of capital costs, depreciation, taxes, and maintenance. Pro offered no evidence that power companies want to deal with the fluctuating inputs of excess solar power. They are required by the government to take the power as a subsidy.It's also not true that a smart grid is already in place. There are so few homeowners feeding power into the grid that they effects are negligible. Having many homeowners doing it would require a massive redesign.Neighborhood utilityPro says that he could come up with a system that sells electricity to his neighbors. That is establishing a new electric utility, subject to the state laws that govern electric utilities. The power company can refuse to connect to you and your neighbors, so you will have to provide your own primary generating capacity. If you do that with solar, no one will need the excess power, because you will all have the excess at the same time. You will need to buy a gas turbine that can be decreased in output when excess solar power is available. The costs of siting, capital, taxes and insurance for that must be figured. You must also wire your own local grid.Home valuesPro claims that home renovations that save energy add value to a home. Renovations that save energy include adding insulation, converting to double paned glass, upgrading to appliances, The reference says the house value increases $10 to $25 for every $1 reduction in annual fuel bills. The solar electric system produces little or no reduction in annual fuel bills because the tax, insurance, and maintenance expenses alone are about equal to what the electric bill would have been. The system itself adds some value to the house, the most at the start and depreciating to zero, but there is no gain from paying the upkeep costs rather to the electric bill. Grid purchase of electric starts at $1404 and solar upkeep at $1458. After some time the power gets to be a little more expensive than the maintenance. What is the value of an asset whose main function is to convert utility bills to upkeep bills? I think it is worth nothing.What the system is actually worth over time will not affect your real estate tax. The government uses your building permit to evaluate the cost of the improvement and increase your taxes accordingly.Do-it-yourselfPro is carrying along a hypothetical do-it-yourself free-labor alternative. Many wonderful savings can be achieved with competent free labor. Auto, plumbing, and appliance repairs all become free, for example. My question is what is our homeowner doing that enabled him to save up a minimum of $44K in free cash for the purchased equipment? If the answer is that he cannot save up the cash, then we should add the interest charges for borrowing the money, at something close to credit card rates. If the answer is that his income is so large as to permit lots of savings, then he is probably better off doing what he does for a living and buying the system. I made this argument in the last round, and Pro did not respond.The bottom line: Home solar is 5x grid powerPutting the revised initial solar cost into the spread sheet, if the money were invested rather than put into solar, after 25 years there would be $214,000 in the account, and $59,000 worth of electricity would have been purchased from the power company.Including the cost of capital, the solar electric system cost would ($90K + $214K - $10K)/$59K = 5.0 times the grid cost.If you buy the idea of free labor for installation and accept Pro's very low battery costs, the account balance for the grid alternative drops to $97,000. Solar is then ($44K + $97K - $10k)/$59K = 2.2 times the grid cost. However, if the "free" labor were hired out and the money invested, the advantage of the grid would be back to 5x.Now, if can keep Pro and Con straight, the resolution is negated. The grid is much cheaper.