Battery types

A wide range of different battery types are available, each with different performance characteristics and varying costs. Battery technology is changing very fast, and new types are constantly coming onto the market. It's impossible to describe the myriad types here. If you need batteries, contact any dealer, such as Real Goods at www.realgoods.com, and ask for technical assistance. By far, lead-acid batteries offer the best performance versus cost for large energy-storage applications. These...

Breezeway Directing Wind within Your House

Optimizing air movement in and around your house Using solar-powered fans in various locations around your home Building a solar-powered space heater m Mnless you live in a perfect climate, heating and air conditioning make up the largest component of your power bill. Ultimately, what you're buying is nothing more than comfort, because you don't need air conditioning and most of the time, you don't need heat. But comfort comes from more than just air temperature. Humidity is a factor, and...

Buying an Existing Solar Home

Unfortunately, not too many solar homes have been built yet. This is going to be changing quite a bit as solar power catches on, but the reality is that if you want a solar home, you're going to have to look long and hard, and you may be disappointed with what you find. You can build your own solar home (see Chapter 19), but that's a long, difficult undertaking. Solar communities are springing up around the country. All the homes feature both passive and active solar, and the designs have been...

Calculating needs

Table 18-1 shows the sample power load for the California cabin (see Chapter 2 for a list of typical power draws for different household loads). Table 18-1 shows the sample power load for the California cabin (see Chapter 2 for a list of typical power draws for different household loads). Energy Consumption in an Off-Grid Home With this chart, you can do some of the following calculations for your load analysis. To calculate the last column, simply multiply the first two columns. Adjustment for...

Catering to the prevailing winds

Prevailing winds are the most common wind speed and direction in your area. Typically, prevailing winds come from the southwest in the summer and the northwest in the winter. Some areas have very consistent prevailing winds, but other areas experience changes almost daily. You may already have a good idea what the prevailing wind is at your house, but you can refine your understanding by keeping a log say once a day for a month (and then one month out of each season, because prevailing winds do...

Checking out a sample electric bill

The best way to illustrate how to do an energy survey is to use Bill Toomuch as an example. Figure 2-1 shows a typical sample from Bill Toomuch's utility bills. Here's a list of some of his energy costs His utility company is PG& E, in Northern California. He uses 3 gallons of gasoline a month in lawnmowers, leaf blowers, and so on. That's around 8 per month, year round. He uses 15 per month in propane for his barbecue, and because he's in sunny California, the usage is consistent over the...

Choosing locations for window coverings

Window coverings are a great way to control the amount of light that comes in and to create an insulating or cooling effect in your home. Figure 9-1 shows your different window covering options, and Table 9-1 explains what happens with each one. With a blind inside, you can get the best insulation. However, the heat is inside because sunshine comes in through the window and strikes the blind. The gap between the blind and the window can get very hot because of the greenhouse effect. This result...

Contents at a Glance

Part J Playing the Energy Chapter 1 Helping the World through Solar Chapter 2 Surveying Your Household Energy Efficiency and Use 19 Chapter 3 Making Your Home Energy Part JJ Understanding Solar Just the Facts, Ma'am 59 Chapter 4 Working with Solar Chapter 5 Evaluating Your Solar Chapter 6 Calculating Payback on Your Solar Chapter 7 Installing Your Solar and Medium-Sized Chapter 8 Digging In to Landscape Chapter 9 Jumping In to Small Projects with Big Chapter 10 Heating and Purifying Chapter 11...

Creating a Simple Homemade System

A simple homemade solar pool-heating system, as shown in Figure 11-4, performs ideally, and you can build it entirely on your own. You lower the submersible pump into the pool water so it'll always be primed. The pump runs off the 12VDC that the PV module supplies. The amount of water the pump passes through the solar collector panel depends entirely on how much sunlight is incident on the PV module At night, the pump doesn't run at all. On cloudy days, the pump runs slowly. When it's sunniest,...

Deciding on the Size of Your Collectors

The general rule is to use a total collector surface area that's about half the surface area of your pool. But this varies quite a bit. Sizing your collector surface area depends on a number of factors I The pump's running time The longer it's on, the more heat you collect in the pool for a given collector size. So you can use less collector size if you run the pump longer (up to a point you still need sunlight, and if you run the collectors for too long, the sunlight won't be available)....

Diving In to Swimming Pool Projects

Checking out the pros and cons of swimming pool-solar heaters Increasing your pool's energy efficiency Considering simple and complex heating systems and doing some projects lmost everyone wants to conserve energy and help reduce greenhouse gases. Certain energy expenditures, such as driving, heating, and lighting, are just plain necessary for most people (although you can still reduce them). Others, including swimming pool heat, are entirely optional creature comforts. If you adopt the energy...

Effort and upkeep

Making good decisions about solar power can be difficult unless you've done your homework. And not only do you have to do some research, but you also have to work with the equipment itself. Here are some issues to consider You face some dangers. Active systems can shock you if you don't know what you're doing. Water heating systems can scald you. You're much safer sitting in front of your TV than climbing around installing solar equipment. You face equipment challenges...

Erasing your carbon footprint

The worst offender is coal, and the United States gets around 50 percent of its electrical power from coal-fired plants. Your carbon dioxide footprint is a measure of how much carbon dioxide you're releasing into the environment by virtue of your energy-consuming habits. A typical carbon dioxide footprint is around 36,000 pounds (18 tons) per year. That's a lot Solar, however, has no carbon footprint. For each kilowatt-hour (kWh) of energy-generating capacity...

Evaluating Your Hardware

As with any hardware, you can nitpick the details and dissect the performances of individual components in order to compare operations and efficiencies. But if you purchase your system from a quality contractor, the staff will have chosen the best equipment for you simply because it's in their best interest. (You don't need the technical details, but if you want to study them, get data sheets from the contractors and go for it.) Reliability is of utmost importance, but you can't get this from a...

Following design and building tips

A do-it-yourselfer can design and build a solar room for a relatively low cost, with relatively low risk. You don't need electrical wiring or plumbing, and you don't need to obey all the building code requirements that are unavoidable inside of a house. You can work through a project without having to apply for building permits or to have the property value reappraised (with the commensurate increase in property taxes). Simply build the room against the house, but don't actually connect it to...

Getting Creative with a Solar Powered Sprinkler

Of all the great toys and gadgets the world of solar offers, the clear winner for most fun is the solar-powered sprinkler. Consider this project a bonus, the 11th installment in a list of ten items. Here's how it works. You connect the unit (including the sprinkler head and motion detector) to your garden hose and sprinkler and stake it firmly into the ground. Then turn the faucet on. When the motion detector senses movement, the sprinkler discharges a blast of water then it turns off. The...

In this part

Although solar energy is responsible W for what grows on trees, it's not money, so you have to look elsewhere. Fortunately, you can find a lot of sources, particularly within government agencies, that are interested in promoting solar power. In this part, I show you how to do Internet research for potential sources of subsidies, tax breaks, rebates, and the like. And I give some good advice on how to work with banks and other financial institutions when the time comes to apply...

Incentives for homeoperated businesses

The incentives for businesses are even greater than those for residences, so if you have a home business or office, you may qualify for higher tax credits and rebates. Why One reason is that businesses use most of their energy in the middle of the afternoon, so they're less apt to go for solar energy when there's net metering (see Chapter 17 for more on net metering). Another is that the green spirit that motivates many solar investments (thereby making the investment more attractive than mere...

Leasing solar equipment

In one new idea that's taking hold, companies install solar equipment on your roof, but they retain ownership of the equipment. You lease the equipment from them for a fixed monthly cost or a percentage of the system's production, which works nicely if you save more on your power bill than the monthly cost of the lease. Or alternatively, you can use these programs to lock in the cost of your energy so that when it rises, you won't be bitten like everyone else. You don't have to have any cash...

Location Location Orientation

Everybody's heard the realtor's favorite maxim, Location, location, location. With solar power, this consideration becomes slightly modified, and orientation becomes a critical factor. You're going to have to be a lot more fussy about your lot when you build a solar house. You want a piece of land that allows you to orient your house with a good southern exposure for PV panels and water heating collectors, and also for windows, sunrooms, and living spaces. On some lots, this is very difficult...

Looking at the Various Systems

A wide range of supplemental water-heating systems are on the market, but only three which I discuss in the next section have stood the test of time. You can install any of them yourself, although you may not want to. Even if you intend to have a pro do the installation, make sure that you understand the various alternatives in order to make the best decision on which system you want. You also need to understand your system in order to get the most out of it. In this section, I explain your...

Looking for Sustainable Energy

The words renewable and sustainable are being knocked around quite a bit, and both are strongly associated with energy conservation. Renewable forms of energy constantly replenish themselves with little or no human effort. Solar energy is just one example no matter how much you use, the supply will never end (okay, it may end after billions of years, but your using solar power won't make the sun burn out any faster). Other examples of renewables include firewood, water (through hydroelectric...

Making Your Own Collector

This project has you make your own collector out of black, plastic landscape tubing. If your collector gets broken, you can fix your collector in a jiffy, which can't be said for commercially available collectors. Combine your collector with a PV-driven submersible pump system (see the preceding section), and you can have a very effective solar pool-heating system for a very cheap price. And you can do it all yourself First, gather your tools and materials 1 Black, plastic landscape tubing For...

Making your reading lamp go offgrid

If you like to read, you can spend 50 to get a small, battery-charged light (LED) that works for four hours on a four-hour charge. A PV module with a length of wire attaches to a battery light switch housing with Velcro backing. Apply the matching Velcro anywhere you may want light. During the day, plug in the PV module and set that in the direct sunlight. At night, press the light into the Velcro and use it. Solar lamps put out a lot of light, but it's focused on a spot. The trick is to get...

Peeking In on a Real Life Scenario

In this section, I walk through some of the calculations for an off-grid home in the mountains of Northern California. Here's what you need to keep in mind about this scenario i The duty cycle is 100 percent, and the house is used year-round. i Worst-case expected sunlight per day is around four hours. i A two-day power reserve is required because the backup generator is 20 years old and may or may not start, depending on its cantankerous mood. There may be some days when power is simply not...

Plumbing and electrical work

Avoid plumbing or electrical work if you don't understand the code requirements or safety hazards. For example, any power system that puts out 120 volts AC is potentially dangerous. If you don't understand high voltages and how you can get a shock, don't mess around with this stuff. At all. Bad installations can create dangers that don't have to be. Books can take you only so far into the project world. Experience counts. This doesn't necessarily mean you shouldn't try something you've never...

Reaping netmetering rewards with timeofuse rates

In some regions, net metering is even more advantageous because the utilities have what's called time-of-use (TOU) rate scheduling in which electricity rates are highest from noon until 6 00 p.m. (peak time). (For info on other rate structures, see the later section called Working with different utility rate structures.) The rate during this period can be over three times the rate at other times (off-peak). This rate scheduling works extremely well for intertie PV systems because that's when...

Red tape and aesthetically minded neighbors

You may have to work around building codes. Bureaucrats are a big hassle, and interfacing with government agencies is frustrating. In addition, only qualified contractors should install complex electrical systems. Also, most solar panels are ugly. Nobody wants to look at them. If they're your own and you're benefiting, it's acceptable. If they belong to your neighbors, it's a different story. In some communities, solar panels are forbidden. Many CC& Rs prohibit solar panels altogether, but...

Researching All the Subsidy Options

Things are changing so fast that it's impossible to keep up with all the government programs. I can only point you in the right direction and give you a nudge. Your job is to poke around and get all the details for yourself. Here's how to research the subject further i Talk to your tax preparer. Tax preparers should be versed in the details of solar tax credits, but if not, they can still access the information sources they need to process your rebates and tax credits. Solar is relatively new,...

Smallscale PV systems Using just a modest amount of power

For 1,000, you can get a solar power system big enough to run anything in your house aside from the major appliances. You can power a home office, where you may be able to write off some costs as a business expense. Or use a solar power system in a remote cabin or a boat cabin or an RV. (For info on large-scale PV systems, see Chapter 17.) About 1,000 can get you 500 watt hours, or > 2 kWh, or a 60-watt light bulb for 8 hours. This is plenty of power to run an office or all the equipment...

Spreading holiday cheer

Running long, snarled power cords to your strings of Christmas lights is a thing of the past. Now you can use solar-powered lights that don't plug in it all. A small PV module charges a battery during the day. At night, illumination comes from low-power LEDs. But they show up loud and clear when they're aimed right. If you want to put up only a string or two, the job takes about 10 minutes. Solar works very well in freezing, clear weather, and the LED lights look great against snow. You may not...

Starting on the design from the outside

Probably the most important factor for getting the most solar bang when building a house is to orient your house in the right direction on the property. The long axis of the house should run east to west for the greatest southern exposure. The front of the house can face south or north. Up to 20 degrees off true south will work well enough. If you've got a squared-shaped house, then you will want to put the family room and kitchen on the southern front to maximize your solar exposure. The other...

Taking advantage of your lots features

When you plan to build a solar house, you want to find the right lot first, and then get busy on the blueprints. You don't want to commit to a particular house design, and then insist on finding a lot that will bear it out. Each lot will support a different style of house with a layout that maximizes views, breezes, landscaping, and so on. So your house design should be a function of the lot. You can take advantage of many of the existing features of your lot as you design your house. When you...

Ten Best Solar Investments

Identifying the best money-saving propositions in solar power Making your house look a lot better Creating a more comfortable home environment n this book, I describe hordes of projects and improvements you can tackle. Your personal situation dictates the type of solar investment that's best for your own home, but some projects stand out because they're practical for nearly every homeowner, in both monetary and aesthetic terms. In this chapter, I give you my list of the ten best solar...

The Different Types of Subsidies

Governments have recognized the value of solar energy, especially in achieving a more pollution-free energy consumption. Plus, solar power has the potential to free North America from reliance on foreign oil, which is desirable from a political stability standpoint. (Getting oil from the Mideast creates a lot of problems.) Governments also recognize the marginal nature of a solar investment, and they've resolved to do something on the cost end of the equation (some politicians may claim to be...

Understanding the greenhouse effect

Everybody's heard of the greenhouse effect (see Figure 16-2) people invoke it to explain global warming, which is one of the big reasons most people are interested in solar energy in the first place. In this case, you want the greenhouse effect to work to your benefit. Greenhouses work by the fact that sunlight enters the space through the windows (which may be plastic or glass or any transmission elements), gets converted into heat by absorption, and then the heat is constrained to stay within...

Understanding Why Solar Is King

Solar power has historically been more expensive than other energy options, but that's changing fast because of government investment in technologies, as well as the simple fact that many more people are investing in solar, which results in economies of scale. Solar energy equipment increases your financial standing in basically two ways 1 Savings on your monthly bills. 1 Appreciation of your home's value. The following sections cover reasons why solar is a great investment, both financially...

Up up and away with the chimney effect

When air heats, it becomes lighter in weight. Cold air weighs more, and hence gravity exerts a larger force on it. So the hot air rises, making the air in a room warmer near the ceiling than the floor. The phenomenon is called the chimney effect because of the way smoke goes up a chimney above a burning fire instead of spreading out into the room. Cold air is drawn into the fire, and the hot air rises quickly up the chimney. The air movement is brisk and consistent because the effect is...

Using a Solar Swimming Pool Heater

When you install a solar heating system on your swimming pool, you can use your pool more than you would without a heater. The water temperature is much more comfortable, and you can swim over a longer season. The average swimming pool costs around 25,000 to install. It takes up a big chunk of your backyard and requires a lot of maintenance. With all the time and money you put into your pool, it's probably the most expensive luxury you will ever purchase. You can use a pool without a solar...

Working with different utility rate structures

If you've ever taken a good look at your power bill, you've noticed that utilities don't speak plain language. Most utilities are publicly regulated companies, which means that their rules of operation are essentially determined by legislators. Low-income customers get subsidies farmers get special rates and residential, commercial, and industrial customers all have different rate structures. What this boils down to a very complicated network of rate structures. But in order to understand...

Working with RV appliances

Small appliances for RVs, boats, and camping are widely available, and any of these work with 12VDC solar power systems. You may even be able to run some appliances without batteries, which makes things a lot cheaper and easier. Heaters don't care how the power looks (it can fluctuate, the voltages and currents can change, there can be ripples galore) how much heat you can generate is all that matters. Fans may blow directly from a PV module the more sun, the harder the fan pushes. Water pumps...

Capacity and efficiency

Battery capacity is a measure of how much total energy a battery can hold. Ratings come in amp-hours (Ah). To get the total energy capacity, simply multiply this number by the voltage. Thus, a 100 Ah battery at 12 volts yields 1.2 kilowatt-hours of energy. In general, the larger the battery capacity, the larger and heavier the battery is. However, the faster you pull the charge out of a battery, the lower the capacity, so the capacity is really useful only for comparing different batteries....

Considering higher costs and maintenance

Chapter 17 details PV electrical generating systems connected to the grid (intertie systems). One of the major reasons for installing such a system is that it lets you sell your excess power back to the utility company. The bottom line is that an intertie system operates at 100 percent of its productive capacity because someone is always using energy as it's being created. Off-grid solar power systems provide electrical power, but it's relatively expensive. When you install an off-grid solar PV...

Understanding Batteries Familiarity Breeds Contempt

After you install a PV intertie system (see Chapter 17), you can completely ignore it for the most part. Keeping the solar panels clean is about the extent of your maintenance. But when you install a system with batteries, you have to stay on top of things. The battery or battery pack is the core of any off-grid system, and it drives the system's cost. All action comes and goes from the battery, and much of the safety and control equipment is designed to protect either the battery or the...

Directing traffic with controllers

A solar blanket for your swimming pool is controlled by applying the blanket or retracting it. You're the controller. Other solar water heaters, however, require temperature controllers that are a little more high-tech. Take a look i A collector connected to your pool pump works whenever the pump is working. The controllers are electric clocks that cycle every 24 hours you adjust the mechanical position of offand on tabs. i Domestic water heater systems often use an electronic controller that...

Solar panels

Climbing around on roofs is statistically the most dangerous part of any installation. Injuries can be severe, maybe even fatal. Do you belong up on a roof Not just climbing around, but pulling heavy weights and tools and going back and forth a lot If you have a flimsy ladder, you're asking for big trouble. After all, solar panels are heavy and awkward. (Imagine hoisting a heavy piece of plywood around in the wind while you're balancing on a roof, and you get the idea.) Solar water heating...

Battery power Charging up your life

PV modules are ideal for charging batteries. The electronics are minimal, and the costs are low because of it. Got an old truck, car, or RV that sits around and doesn't get started very often How about a boat If they've been giving you problems starting, a solar charger may be a very cheap and effective solution. When a vehicle sits around without being started up for a while, its battery grows weak. If the battery is old, it's even worse. For 40, you can get a solar battery charger. A PV...

Battery Chargers

If you use a lot of batteries, you can drastically cut back on battery costs by using rechargeable batteries in conjunction with a solar charger. And I'm not only talking about the standard household batteries, either. You can get solar chargers for vehicle batteries, notebook computer batteries, and small appliances. Using these devices gives you a very good lesson on PV technology because you'll need to locate the PV panel in a good, sunny spot to get the most juice into your battery.

Understanding Off Grid Ramifications

You have choices when you go off-grid. Propane works well for heating and cooking and refrigeration. Wood stoves are popular for remote houses and cabins because there's usually a ready supply of firewood. But at some point, you're going to want to plug in your television, and the choices are more limited. Gas-powered generators are inexpensive and can put out a lot of power when needed. But they're noisy, cumbersome, and smelly, and they pollute quite a bit. If you're out in the middle of...

Plugging In to the Grid with a Full Scale PV System

Understanding the benefits of large-scale PV systems Knowing how net metering works Looking at the components of a large-scale PV system Figuring out payback Contracting and getting the job done properly installing a full-scale intertie system at your home is the king of solar investments. You can offset your entire electric bill, at essentially zero pollution. The cost is high, more than 8,000 anywhere up to 100,000. For some, it's a simple decision because the main goal is to eliminate...