Dear Dr. Gridlock:

As one of the first local drivers of a hybrid (Toyota Prius), I wanted to report some real (not estimated) mileage figures. I've driven my car 18,317 miles on 410.5 gallons of regular gas, for an average of 44.6 miles per gallon (costing an average of $1.42 per gallon).

I love it! Two endearing things: It re-burns its exhaust so that what finally comes out has less than 2 percent of the pollutants coming out of the average car (qualifying as SULEV -- super, ultra, low emission vehicle), and it turns off the gas engine and uses the electric engine when stopped or starting up -- really a silent runner!

P.S. I am a curator at the National Museum of Natural History. Our staff now has seven hybrids -- six Priuses and one Honda Civic hybrid!

Dan H. Nicolson

Arlington

Dear Dr. Gridlock:

I have owned my Prius for over a year, and it has seen all kinds of weather. It has wonderful mileage and snow traction. Its only deterrent is that it is low to the ground and does not like snow piles rubbing its belly.

Its power and pickup are equal to any, and its mileage is superb. It hugs the road and corners well. My previous car was a Jeep.

Lois Walker

Alexandria

These are encouraging reports!

Dear Dr. Gridlock:

You asked how drivers are enjoying the hybrid vehicles. We bought a Toyota Prius in October, and I am using it on my daily commute on the Fairfax County Parkway. I couldn't be happier.

It is designed for the type of driving the parkway demands: medium speeds (usually), lots of stopping and starting, etc.

It is great in traffic jams because it just shuts off and quietly waits until it is time to go again (that was a little unnerving at first). The fuel consumption seems to be dependent on the temperature more than in a regular car, since my mileage is running about 47 mpg in warmer temperatures and nearer 42 mpg in the frigid cold weather.

The car is comfortable for our three-person family to use on weekends, and great as a commuter car. I don't feel guilty about my single-person commute anymore, and it's cute!

Jenny Pate

Springfield

Few things in life are as satisfying as owning a car you love.

Dear Dr. Gridlock:

In response to Brian Broadhead's "Hybrids' Fuel Efficiency Goes Only So Far With One Occupant" [Dr. Gridlock, Feb. 27], I have to point out that Mr. Broadhead is grossly uninformed as to the efficiency of hybrids.

Mr. Broadhead asked: "What pollutes more, three people sharing a ride in a car that gets 25 mpg, or three people each riding in their own hybrid getting 40 mpg?" Mr. Broadhead needs to perform a simple mathematical calculation. Which is better for the environment, a regular car with two to three occupants, putting out 100 percent of the pollution that a regular car puts out, or a hybrid with one occupant putting out 10 percent of the pollutants of a regular car?

The question is asked, Why should hybrid owners get special HOV exemptions when Mr. Broadhead doesn't? It's because we get better mileage and put out 10 percent of the pollutants of a regular car.

My Toyota Prius averages 45 mpg. While driving solo in the Interstate 66 HOV lanes during rush hour, I have seen a man and woman in a large black Ford SUV hold up a sign that says "HOV-2," with the man then holding up two fingers. In return, I smile and hold up one finger. Guess which one?

What should be banned from HOV lanes are large SUVs and smelly diesel vehicles.

Bob Cochran

Reston

Dear Dr. Gridlock:

Brian Broadhead's comments [Dr. Gridlock, Feb. 27] regarding emissions prompted me to write. Even before the current rise in prices, I had been tinkering with the idea of purchasing a hybrid car to ease the fuel cost of my 60-mile reverse commute from Gaithersburg to Owings Mills, north of Baltimore. I noticed that every hybrid I looked at received a SULEV rating, so I did some research and found the actual emissions standards at www.cleancarcampaign.org.

The SULEV standard requires less than 1/30 (a 97 percent reduction) the emissions of the current federal standard for some pollutants. Broadhead states, "What pollutes more, three people sharing a ride in a car that gets 25 miles per gallon, or three people each riding in their own hybrid getting 40 mpg? The answer to that should be pretty obvious."

It sure is. Three hybrids produce less pollution. Hybrid cars use half as much or less gas and pollute far, far less. One Web site, www.autotestreport.com, broached the question of how to test emissions when vehicle exhaust is cleaner than the ambient air.

D.C. does have horrible traffic congestion, but it also has horrible air. Because federal road-building dollars are connected to clean air, Virginia is trying to improve both with its HOV program. I say let the exemption for hybrids stay.

Cary Abend

Gaithersburg

Dear Dr. Gridlock:

I commute from Lake Ridge to D.C. via an OmniRide bus. If I were to purchase a hybrid car, I could and probably would drive to work via the HOV lanes.

Because the bus I ride would continue to operate without me, the net effect of my action would be to increase the amount of pollution and fuel burned, because I would be adding a vehicle to the HOV lanes that previously didn't exist.

In fact, if just one person from every commuter bus and vanpool were to buy a hybrid and drive to work, the net effect would be a significant increase in the amount of fuel burned and pollution generated because of the increase in the number of cars on the road. Remember, not everyone commuting on the HOV lanes can afford a hybrid -- or any car, for that matter -- and they rely on public transportation to get to work. Buses and vanpools will not be replaced.

Some will argue that commuters who drive alone on the regular lanes and replace their gas guzzlers with hybrids to use HOV lanes are helping to reduce pollution and fuel consumption -- this is true.

But at some point, so many people will replace their gas guzzlers with hybrids and opt to use HOV that the increase in congestion will negate the decrease in pollution and fuel consumption.

An increase in cars on HOV will increase congestion in those lanes, resulting in longer commutes for everyone. And because pollution is directly related to fuel consumption, the longer cars, vans and buses will have to stay in congested traffic, meaning the more fuel they will burn and the more they will pollute.

We do need hybrid cars to help reduce pollution and fuel consumption, and the government needs to keep providing incentives for their purchase. But granting HOV exemptions to hybrids is not the answer.

Bob Clements

Lake Ridge

One of the balancing factors here is that some bus riders can't afford to buy a hybrid vehicle, at $22,000 to $25,000. Others, I suspect, would rather let someone else do the driving and would stay on the bus.

We'll be monitoring the arrival of hybrid vehicles in our commuting patterns and measure the effect.

Escalator Headaches

Dear Dr. Gridlock:

Every time I take the Metro, I seem to encounter escalator problems. The problem will never get solved until there are consequences for not resolving the problems -- i.e. fire management, fire the union, or both -- and outsource the maintenance.

I'm reminded of an ice skating rink in New York City that city folks had been trying to stop leaking for eight years. Donald Trump volunteered to solve the problem and did so in less than three months and substantially under budget.

D.C. continues to remain a "broken system" because nobody has the political will to solve the problems.

Hal Van

Ashburn

Consider this: The chief executive of Metro is not elected. He is appointed by the Metro board, that in turn consists of local elected officials who rotate through the board positions.

It is difficult for the electorate to figure out who is responsible for such poor performance and exercise their feelings at the ballot box.

I'm afraid the current system encourages the status quo.

Dear Dr. Gridlock:

I'm a native Washingtonian returning to D.C. after 27 years in Chicago, and trying to use the Metro as much as possible. Because I'm often carrying my laptop and other material, I really rely on the escalators at Metro stops. I'm finding that maybe half of them don't work. Then I've either got to climb them or wait for the elevator, if there is one.

What percent of the escalators are not working and why?

Mel Schnapper

Washington

Metro for years said that 95 percent of the escalators were working at any given time. But the experience of the readers seems to find them much more unreliable than that figure suggests.

Why? Escalators exposed to the elements and union maintenance crews that lack sufficient training have been mentioned among the causes.

Metro has to figure out a way to fix the escalators, or risk losing credibility with its customers.

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in Alexandria Arlington Extra. You can write to Dr. Gridlock, 1150 15th St. NW, Washington, D.C. 20071. He prefers to receive e-mail, at drgridlock@washpost.com, or faxes, at 703-352-3908. Please include your full name, town, county and day and evening phone numbers.