Water heaters

Don’t install a solar water heater if you don’t understand its engineering, par-

ticularly its dangers and maintenance requirements.

Water heaters can be problematic in hot weather. When a solar panel sits in

the direct sun long enough, the water can sometimes rise to over the boiling

point. Solar panels have been known to rupture from steam pressure, which

can burn (not to mention cost a lot to fix). Or the pipes can fill with super-

heated water and burst inside your house.

 Always keep children away from solar water heating systems and the associ-

ated pipes. Also, add some safety measures to your valves. Most solar water

heaters have valves for controlling flows and evacuating equipment for vari-

ous reasons, such as performing maintenance or keeping water from freezing

in the pipes in cold weather. Children love to play with valves, so buy valves

with padlock loops to prevent children from reaching up and twisting a valve

with superheated water.

Batteries

Batteries are safe, effective, and reliable when used properly, but they can

also cause worse injuries than electrical shocks. If the terminals of a big bat-

tery get shorted, a tremendous arc of current flashes, precisely the same as

an arc welder. You don’t want to be around when it happens.

Unsealed batteries can emit noxious fumes. They can corrode, so take special

precautions when you dispose of them. In order to wire up a safe and effi-

cient battery circuit, you need to know exactly what you’re doing.

 Buy a system with batteries in complete form — all these battery dangers

should be adequately addressed.Parts list

You generally want to build the reservoir parts of the fountain before selecting

a pump, so buy the materials in two stages. Here’s what you need to build the

basic structure of the fountain:

 ✓ Two halves of an oak barrel: These cost $20 and up per half at big

nurseries. Nice barrels from wineries cost more, but they’re very good

quality and usually look better for a lot longer. They’re not easy to cut in

half, so buy them precut.

 ✓ Clear silicon sealant: Seal cracks and leaks with clear silicon sealant,

sold at all hardware stores.

 ✓ A completely reliable support structure: Use heavy, rigid concrete blocks

or bricks to support the upper reservoir, with the bottom around an

inch higher than the top of the lower — it can get very heavy, so keep safety

in mind. Keep the upper reservoir as level as possible. The lower barrel can

sit on the floor, with the back edge supporting the upper reservoir.

 The upper reservoir can weigh upward of 200 pounds if you’re using big

barrels. If you don’t get it set with integrity, it can come crashing down.

Always use concrete or mortar or glue whenever possible. If you need to,

make the structure rigid enough so a kid can climb onto it without mishap.

 ✓ A valve (faucet): For $8 you can get a good brass faucet. Even better, gift

shops often sell fancy faucets made of copper (green patina). Faucets

made for outdoor hose systems come with male-threaded mounting

ports, so you can screw the faucet into the barrel after you drill a hole.

 ✓ One copper tube, around 4" long, between 1

⁄2" and 3

⁄4": Copper tubes are

stock items in plumbing departments.

 Or you can use a decorative valve that matches the other one as your

overflow spout. Just open it up all the way and leave it like that.Your biggest decision is how large to make the upper reservoir. The larger

the reservoir, the longer the capacity (in time) to continue flowing without

sunlight on the solar panels. Then again, you don’t need an upper reservoir

at all — if you go without, your fountain goes exactly with the sunlight, and

you can hear how much sunshine there is at any given time.

Deciding how much power you need impacts cost the most. For more power,

you need both a bigger pump and a bigger PV module. Tall fountains require

more expensive pumps and PV modules to move the same amount of water.

 Try to go for subtle. If you want to make up for lack of flow, make a lot of little

fountains instead of one big one. Make your fountain shallow and broad. The

water levels in narrow, deep fountains change quite a bit, which can be unat-

tractive and cause big fluctuations in the flow levels.

Many landscape fountains use a black rubber liner that fits snugly over

almost any contour. It’s easy to install, seals very well, and lasts a long

time. Unleash your imagination. Broad, shallow reservoirs work better than

narrow, deep ones because the water levels don’t vary nearly as much.

 You have to keep your solar fountain topped off with water because you

can’t let the pump run dry. The easiest way is to connect a drip valve from a

landscape watering system into the lower reservoir (just barely suspend the

dripper over the edge of the lower reservoir — don’t let it hang down into the

water, or it may siphon out your water). Make sure to leave a drainage path

for when the lower reservoir overflows (you don’t want to use this method

if your fountain is indoors or sitting on a finished floor such as tile). If you’re

not getting enough water to keep the lower reservoir filled, use more dripper

heads. Overflow doesn’t hurt the system, but you don’t want the pump to run

dry, which happens when you don’t have enough water. Err on the side of full.

The best fountains blend in with the natural scenery. Use natural rock and

surround the fountain with plants. If you’re interested in creating a natural

ecosystem and using a solar pump to enliven it with some moving water, use

broad, shallow reservoirs, and locate the valve only an inch or so below the

level of the overflow spout. The depths of the ponds will vary only by that

amount.Lighting Your Yard with Solar

One of the easiest and cheapest ways to start out in solar is by installing

lighting in your landscape. For $15, you can get a decent solar light with a

range of mounting schemes. The simplest units come with a built-in stake so

you literally don’t do anything more than stick it into the ground. If it turns

out that you don’t like that spot, pull it out and stick it somewhere else.

The vast majority of solar landscaping lights come one-piece, with the PV

module on top of the light itself, so you should put the whole thing where it

can get a reasonable amount of direct sunlight. However, solar lights may

surprise you by how well they work, given a meager amount of light. If the

lights don’t get much sun, they still come on at dusk — they just don’t last

all the way to dawn. Your best bet is to try one out in the location you want,

even if no direct sunlight is there. It may work just fine.

Some lights are static, meaning they don’t blink or change colors.

Background lighting, for example, should be static; it should establish a sense

of place and highlight the best features of the environment. The most func-

tional locations for the spotlight variety are around porches and walkways

and along driveways where people will be walking. Put one near your garbage

can out back, and you don’t have to flip the light switch anymore. You can

also get solar lights connected to motion detectors (see Chapter 9).

Other lights revolve through patterns of color and brightness. The effect is

entirely different. Dynamic lights should add a subtle hint of presence. One of

my favorite solar lights is a clear plastic butterfly that changes colors slowly

and subtly. It comes on a stake with a 2-foot wand to the butterfly, which

seems to be floating because you can’t see the wand at night. It draws your

eye without demanding it, and the colors are rich and textured.

 Don’t buy cheap lights, because they don’t last. If it’s in a flimsy plastic hous-

ing, don’t buy it. Aluminum is good; heavy black plastic is cheaper and works

just as well. You may want to buy an entire matching set; 6 units for $60 is

usually good quality