A new Q&A feature by environmental engineer Vern Novstrup.

Dear GreenLight,

I currently own a home with a solar hot water system. The panels will have to be removed as part of reroofing work. I've been told by the contractor that the removal and reinstallation of the solar panels will cost about $600. The contractor suggested that I get rid of the system because solar hot water systems tend cause roof leaks and are not cost-effective anymore. The system is about 20 years old but seems to be working fine. Is it worthwhile to reinstall the panels?

-- R.M.


  Dear R.M.,

Spending $600 to keep an existing solar hot water system in most cases is a good investment. Depending on your water usage, you may be saving up to $200 annually, so you can reasonably expect your investment to pay for itself in as little as three years. If you abandon the system, you still will have to spend money to remove the panel, storage tanks, and reroute plumbing. Those costs will be less than $600 but will still be significant. Solar hot water heating systems only tend to cause roof leaks if they are improperly installed (usually by an unqualified contractor). To be sure you don't have any problems, I strongly recommend you contract the removal and reinstallation portion of the work to a qualified solar company. While you are making changes, I'd also suggest you have the solar contractor evaluate the system to see any system changes are justified. For example, if your panel is nearing the end of its life you may wish to install a new panel rather than waiting for the older panel to fail. Keep in mind that many of the older systems were constructed of heavy weight copper that may still be in very good shape.

 Dear GreenLight,

The other day someone mentioned to me that the EPA is going to require that all SUVs pollute less. I own a newer minivan. How will the EPA rules affect me?

-- B.B.


Dear B.B.,

The new rules will only affect SUVs manufactured in model year 2004 and later. So the only impact on you will be having to wait until 2004 to see the benefits of the new regulations. Even then the impact will be insignificant in Southern California because California already has tough emission standards for new SUVs.

Also, as EPA develops new regulations, they assess not only potential benefits but also technical feasibility. As a result you can bet the regulation is fairly reasonable and will have very little impact the overall quality of SUVs. In fact, many of the technologies that make modern cars more reliable were developed to meet either emission requirements or fuel economy standards. The cost of new SUVs may go up a few hundred dollars. However, considering that an average new SUVs sells for something like $25,000, I doubt an extra $200 will change buying habits.

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