Название: Solar Water Heating--Revised & Expanded Edition
Автор: Bob Ramlow
Издательство: Ingram
Жанр: Техническая литература
Серия: Mother Earth News Wiser Living Series
isbn: 9781550924497
isbn:
Figure 1.1: US energy consumption, 2008
In Figure 1.1, you can see the breakdown of the total energy consumption for the US in 2008. Renewable energy accounted for only seven percent! Solar, both thermal and electric, made up only one percent of the renewable energy share — only 0.07 percent of the total.
Now that we’ve covered history and the present, we need to look at our future. If what happened in the past carries on through tomorrow, we are headed down a dark and dirty path. One percent of only seven percent is not good enough and needs to change now. Let’s do all we can to make our children’s future brighter.
2
CONSERVATION AND THE ECONOMICS OF SOLAR WATER HEATING
WHATEVER BROUGHT YOU to this point, whether it was the realization that we are trashing our environment or the simple need to lower your living expenses, now you are here and you want to do something. But what to do first? The answer is simple: start by conserving the energy you use to heat water. Three general principles that are easy to follow will also save you money: reduce losses, increase efficiency and reduce consumption.
To start, examine your heating system from top to bottom and look for places where heat might leak out. Heat losses in the system end up wasting the energy you just used to heat your water. Many losses can be reduced with just a bit of cheap insulation. For instance, insulate all your hot pipes. If you are working on a new construction, insulating the hot pipes is easy. Even if you don’t have access to all your pipes, insulating the ones you can get at will make a noticeable difference. You should also insulate your water heater. A tank type water heater heats a whole batch of water. As this water sits there waiting for use, it slowly cools down. The more you insulate it, the better it will retain its heat. Heat losses can also come from leaks. A faucet that leaks 30 drops of water a minute will waste almost 100 gallons a month. Fix leaky faucets promptly.
Next, try to increase the efficiency of everything in your home that uses hot water, for instance, the washing machine and the dishwasher. Upgrading these appliances to more energy-efficient models will significantly reduce the amount of energy consumed. A frontloading washing machine uses half the hot water of a standard top-loading model. This results in saving 10 to 20 gallons of hot water in each load you do. You can save thousands of gallons of hot water a year.
Finally, you can conserve energy by simply using less. Former US Vice President Dick Cheney is famously quoted as saying that the “American way of life is non-negotiable.” We couldn’t disagree more. Simple behavior modifications can dramatically reduce the amount of energy we consume without a significant change in daily habits. For instance, when washing dishes in the sink by hand, don’t let the water run while rinsing. Fill one sink with wash water and the other with rinse water. Soak pots and pans instead of letting the water run while you scrape them clean, and if you are using a dishwasher, wash only full loads. Use cold water with the garbage disposal. Cold water solidifies grease, allowing the disposal to get rid of it more effectively. You can take short showers instead of baths. You should first install a low-flow shower head. Most standard showerheads use three to four gallons per minute. Even if you take a relatively brief five-minute shower, you can consume 20 gallons of hot water. Low-flow showerheads will use half of that. A family of four can save well over 1,000 gallons a month. If you are particularly attached to your showerhead, you can install a flow restrictor that will reduce the number of gallons per minute that it uses. For only a couple of dollars, you can reduce your load substantially.
Reducing losses, increasing efficiency and reducing consumption: these are the first steps. More important than quick fixes, though, is the notion of conscious consumption. We have forgotten the financial and environmental costs of hot water. If everyone recognized that whenever we turn on the hot water faucet we are using energy produced by nonrenewable sources, this would reduce energy consumption more than any other measure.
People often say to us, “I have done a lot of energy conservation and now I am ready to invest in a renewable energy system. What should I do next?”
Today, homeowners and business people can choose from a wide range of renewable energy technologies. Popular options include photovoltaic (solar electric) systems, wind electric systems and solar water heaters. In almost every case, a solar water heating system is the best place to start. It provides a higher return on your investment than most other types of renewable energy systems. A solar water heater works 12 months a year, providing hot water to your home or business with little or no additional cost, thus offsetting your previous bill for heating water with conventional energy sources. Depending on your particular situation, the savings in conventional fuel can pay for the cost of the solar water heating system in as little as three years. Most often the payback is five to ten years — still a great investment, even without taking into account the ecological benefits of not burning all that fossil fuel.
In fact, since you’ve already bought this book, it’s time to let you in on a little secret. Solar water heaters don’t cost anything. They’re FREE! Of course, it may sound absurd, but it’s true. Now, we’re not recommending that you run over to the nearest solar distributor and just take a system. Don’t do that. We are just asking you to take a step back and think about solar in a different way. With a little change in perspective, you will see that in the end, solar water heaters have a net cost of zero dollars.
There are two ways to take this in. The first one is easy: when you install a solar water heater you are increasing your home’s value. You gain in equity what you spent on the cost of installation. Many solar water heaters have a life span of 30 to 40 years, and sometimes longer. In most cases, the solar collectors will outlast your roof. So if you decide to sell your home, you should get back most of what you paid for the cost of installation. Though there isn’t a lot of data on this fact, the general rule we have seen is that for every $100 in annual energy savings you can expect an additional $2,000 in resale value of the property. For instance, if your solar water heater saves you $200 a year, your fair market value should increase by $4,000. Here in Wisconsin, and in many other states, renewable energy systems are exempt from property taxes. Like any other home improvement, this is an investment, but the added value doesn’t carry an additional annual cost.
Yet, just because something retains its value over time and you don’t have to pay taxes isn’t usually reason enough to go out and buy it. The second part of this shift in perspective takes a bit more explanation, but we assure you it is even more convincing.
The True Cost of Fossil Fuel
We’ll start by comparing solar with the alternatives. Unless you are reading this to find out how to fix your existing system, you probably heat your water with some type of fossil fuel, such as natural gas, propane or electricity.
When you purchase fossil fuels, you do not pay anywhere near their whole cost. Because our taxes subsidize the oil companies, for instance, the true cost of gas is not reflected in the price we pay at the pump. Let us say it again: oil companies don’t pay taxes on all the money they earn, so we must all pay higher taxes to make up for it. It goes without saying that if they paid their fair share of taxes, our tax rates would be lower, and the price we pay for gas would be higher. The same scenario holds true for all СКАЧАТЬ