Sometimes there are incredibly simple solutions to the complex environmental dilemmas facing our planet. All we need is a reminder.

That's what Petaluma-based Daily Acts provides with its annual Community Resilience Challenge, which culminates this weekend with two days of activities. Participants get a check list of simple things they can do to reduce their energy and water consumption.

Today we cover four quick, inexpensive home modifications that require little more than a screwdriver, power drill, ladder and your hands. For a $475 outlay, you can save more than $1,000 a year on utility bills while dramatically reducing your energy consumption.

<b>Install a new thermostat:</b> A programmable thermostat helps you control when to heat or cool your home, reducing your heating and cooling costs by more than 20 percent if you manage it well, according to U.S. Department of Energy estimates. Just lowering your thermostat by 10-15 degrees during the workday (or raising it during the summer) can reduce energy use by 5-15 percent.

A simple Ace brand programmable thermostat costs about $25. I chose a $69 Honeywell unit that offers a Monday through Friday workday setting and separate, variable weekend settings.

Here's how to do it: Turn off the switch or circuit breaker controlling the heating, ventilating, air conditioning (HVAC) unit. Remove the existing cover. Unscrew the wall-mounting plate from the old thermostat.

Take a photo of the wires, or write down the number and colors of the wires, and take that with you to the hardware store to ensure correct model selection.

Install the plastic anchors, then attach the new wall-base plate with the screw-anchors provided. Drill a pilot hole for the plastic anchor using a 3/16-inch drill bit.

Before attaching the new unit, install two AA batteries, then attach the unit to the base plate. Now it's time to turn the power on and program your thermostat.

If you find the directions confusing, locate the nearest tech-savvy teenager and put him or her in charge of programming. (You can also visit the manufacturers website for videos and tutorials.)

<b>Swap incandescent bulbs for LEDs:</b> Light Emitting Diodes are without a doubt the future of lighting. Already common in urban street lights and vehicle headlights, they can cut your home lighting energy consumption by more than 75 percent.

They cost $10-$20 per bulb, but the U.S. Department of Energy estimates that replacing 15 incandescent bulbs can save you more than $50 a year. LEDs use 90 percent less energy than incandescent bulbs and have an average life span of 25,000-50,000 hours.

When shopping for LEDs, you'll notice the packaging lists the equivalent wattage and lumens of comparable incandescent and CFL bulbs. Remember that wattage is an indicator of energy consumption, while lumen is the important value, the amount of light perceived by the human eye.

LEDs come in a range of color temperatures, from warm white to natural, daylight white, cool or commercial white. They also are available for dimmer switch applications.

You can replace traditional fluorescent lighting with LED lights, but that often requires rewiring the fixture and changing the ballast. We'll save that process for a future column.

<b>Change your shower head:</b> Installing low-flow shower heads can cut water consumption by more than 50 percent. If yours was made before 1992, odds are good that it consumes as much as 5.5 gallons per minute (GPM) versus the low-flow models in the 1.5-1.8 GPM range.

A few attractive designer models include American Standard's "Flowise" (1.5 GPM, about $34), which could save a typical family up to 8,000 gallons per year. Others to consider include Delta's "Amplifying" tech-look head (1.8 GPM, about $25) and the elegant commercial-grade Niagara (1.5 GPM, about $10.)

How to install it: Hold the goose-neck pipe in one hand to stabilize it and remove the old shower head with a adjustable wrench. (Always remember, "Lefty loosey, righty tighty.")

Wrap threads of the goose-neck pipe with Teflon tape, wrapping clockwise. Then hand thread the new shower head and firmly tighten it with an adjustable wrench.

<b>Unplug electronics and save a bundle:</b> As much as 75 percent of the energy used by your home electronics and appliances is consumed while they are turned off but not unplugged, according to the Department of Energy. That's because they are ready to spring into action.

Examples include cellphone and battery chargers, televisions, stereos, computers, kitchen appliances, microwaves and CD/DVD players.

Look for the little glowing red or green lights that signal "standby mode," also known as vampire power or phantom load, which accounts for more than 7 percent of all electricity consumed in the U.S.

Solve the problem by pulling the plug or switching off the power strip, an energy vampire of its own.

<b>Other easy fixes include:</b>

Installing a clothesline to line-dry your laundry.

Going "reusable" with water bottles, mugs, food containers, shopping bags and diapers.

Weatherizing your home to plug leaks.

See the full checklist at www.dailyacts.org/crc.

<i>Tom Wilmer has been a licensed general contractor since 1986. Contact him with questions or story suggestions at tomwilmer@aol.com.</i>