The Scoop on Cat Litter

Hey Mr. Green,
What is the greenest kitty litter for my indoor cat? --Carol (submitted via e-mail)

Cats themselves are a much bigger environmental menace than kitty litter. They're an invasive species that kills hundreds of millions of birds and mammals each year, robbing food from native predators like hawks and owls. So I salute you for keeping your feline where it belongs: inside.

The greenest cat litter is made of recycled paper, followed by sawdust, wheat chaff, oat hulls, or other biological materials. But more than half the litter in the United States is made of bentonite--a stripmined clay that leads right to Dick Cheney, which may explain why he raked around in Iraq like it was his personal litter box. Halliburton, where Cheney was CEO, produces about one-sixth of the 3 million tons of bentonite sold each year, of which 1.7 million tons go into cat litter. Quite a waste of a substance that can be used in iron smelting, environmental cleanup, and wine clarifying.

Neither bentonite nor silica gel litter should be flushed en masse, as they can gum up plumbing, but flushing a few particles probably won't cause trouble. Most municipal sewage systems can handle pet waste, but it should not be flushed where sea otters live, since studies have found some of these animals to be infected with toxoplasmosis, a parasitic disease carried in cat feces. Because this parasite can severely harm human embryos, pregnant women should avoid handling cat waste.

Saving Money with Solar Power?

Hey Mr. Green,
If I were to put solar panels on my home, would it be cost-effective? I see most solar panels in hot climates, and Ohio can be very cold. I live on a five-acre tract and have the option of wind turbines also. --Sherry in Dayton, Ohio

It may get cold in Dayton, but that doesn't mean you don't get sun. In fact, you get 80 percent as much sunlight in a year as Sacramento, California, whose municipal utility is a leader in solar development.
First, consider the low-tech route: efficiency. The average U.S. household consumes 11,000 kilowatt-hours per year, when many could get by on half as much. Eliminate waste by turning off lights and appliances when not in use, for example, and you could slash your energy costs with no investment.

Wherever you live, take a look at returns over the long haul. At $9 a watt, which is the typical cost in your region, a solar energy system large enough to generate power for an average household would cost roughly $80,000 after rebates and tax credits (or less in areas with stronger incentive programs). In Ohio, as in most states, if you generate more than you use, your excess power feeds into the electricity grid and you earn credit for it, allowing you to draw out as much as you put in--for free.

Still, it would take about 30 years for you to break even, assuming the utility rate goes up 4 percent a year and you put money saved from your energy bills into tax-deferred investments. But you'd keep more than 260 tons of greenhouse gases out of the atmosphere over the life of the system.

Once you nail down the cost per watt for solar, contact wind power dealers and see how their costs compare. It's hard to be more specific about wind power because there's so much variation, depending on windmill height and local topography. You might also consider systems that combine wind and solar if wind blows much harder in the winter than in the summer. These hybrid systems take advantage of seasonal variation. Meanwhile, be thankful that Big Oil hasn't privatized the sun and forced us to pay for it right down to the last photon.

Flushing Out Alternative Toilets

Hey Mr. Green,

There are a lot of folks who live outside urban areas and have private wells and septic systems. How green are these?  Doesn't this essentially recycle the water we consume and flush?

--J. Lennon in Wake Forest, North Carolina

More than 20 percent of the country's households use septic systems. They are the basic choice where there is no municipal sewage system, although I suppose a composting toilet is the ultimate green sewer machine (some are even designed to capture the methane from the waste to burn in stoves). To be on the cutting edge of sludge, you can explore various models on the internet.

Of course, septic tanks have to be pumped out periodically and should be set up to avoid the risks of health problems or water pollution. But if they’re properly designed and installed, I don't see a problem. Since some of the tanks’ water seeps back into the ground, they actually do recycle. For a wealth of information, visit the EPA's website. Your tax dollars at work!

Whatever system you're on, flush minimally so as not to waste water. In my long-ago farm childhood, we had an old outdoor toilet. It was a used model, its wooden walls laced with graffiti so vivid that it jump-started my literary career. When we finally obtained the long-anticipated indoor alternative, my father enforced minimal flushing because of his concern that the well would go dry. With water, as with everything else, the old-timers practiced reduce, reuse, and recycle long before that phrase became an axiom.

Other water-conservation tools that could be used, whether you live in the middle of nowhere or the middle of Manhattan, are: low-flow toilets, restricted-flow showerheads, aerator screens on faucets, smaller lawns and minimal lawn watering, drip irrigation, use of native plants instead of thirsty exotics, and washing machines and dishwashers run with full loads only. (And yes, a modern dishwasher uses a lot less water than a typical hand-washing process.) It goes without saying that you should make sure no faucets leak.

Some people even collect rainwater and use "gray water" (from showers and laundry) on their gardens. But if you attempt these measures, make sure there aren't toxic materials on your roof or in gutters that would contaminate the water – and that the gray water is safe for your plants.

A Real or Fake Christmas Tree: Which is Greener?

Hey Mr. Green,

Have you reached a conclusion on the real tree vs. artificial Christmas tree debate?

--Kathy in Winston Salem, North Carolina

I have indeed. The real tree is better for the environment than the fake tree. A real tree is a renewable resource, whereas a fake tree is usually made from plastic, which is derived from oil, a nonrenewable resource. The real tree can be recycled as mulch, compost, or wildlife shelter, whereas the fake tree can’t. The real tree does not contain harmful chemicals, whereas fake trees are often made with plastic polyvinyl chloride, whose manufacture releases highly toxic material. Plus, lead may have been added to stabilize the plastic. The real tree also absorbs carbon dioxide while it grows, doing its bit to fight global warming.
 
The belief that using real trees causes deforestation is mistaken. The fact is, real trees are farmed, often on marginal land that can't be used for other purposes.
 
I see only two disadvantages to real trees: First, since they have to be shipped from a tree farm each year, real trees require a lot more shipping energy than the one-time shipment of a fake tree that will be used for an average of nine years before being dispatched to the landfill. Though about 85 percent of fake trees are made in China, and thus shipped farther than real trees, they require considerably less energy to ship.

The other problem with real trees is that many farmers use pesticides on them. It’s doubtful, though, that these cause more environmental problems than the petrochemical stew from which fake trees are confected.
Both of these problems can be ameliorated by either buying a tree from a source as local as possible or by buying an organic tree. Find trees closest to home at www.christmastree.org.

There is a third option: a live tree, which you keep in a pot and bring forth with glad tidings to decorate each holiday season. This would seem to be the best choice of all. But don't get a live tree unless: a) you’re absolutely sure it’s a species well-adapted to your climate, and b) you are plant-savvy and dedicated enough to take proper care of it. In my long years of horticultural observation, I've encountered more dead live trees than living live trees.

A final point: I'm for buying the tree as late as possible. This is because, first of all, dealers tend to lower the prices to unload them late in the game, which has great appeal to people as cheap as me. Also, because the frenzied consumerist buildup to the holidays gives me the willies, early tree-purchasing seems more like a celebration of shopping than of anything cosmic or miraculous.