Impact Calculator Upgrades – Solar Hot Water and Air-Dry Laundry

Impact Calculator Upgrades – Solar Hot Water and Air-Dry Laundry

We’re happy to announce that we’ve recently added two new projects to the Low Impact Living Environmental Impact Calculator that show the benefits of air-drying your laundry or installing a solar hot water heater.

First, we’ve added a project that shows how much money, energy and carbon dioxide you can cut by replacing a few dryer loads of laundry a week by air drying. Simply fill in your current number of dryer loads (and your dryer fuel) in the “calculate impacts” section of the calculator, and then go to the “select projects” page. There you’ll find a project titled “Air dry your laundry” (it’s about five or six rows down). Click the “Project Description” link to see all of the details on how much you’ll save. The calculations assume that you air dry 75% of your existing dryer loads. We also show a couple of great drying racks/lines if you’re looking for something a bit better than the standard clothesline.

Second, we’ve added a solar hot water heater option to our list of renewable energy projects. This project takes your estimated hot water use (calculated based on your specific inputs) and the solar resources in your area and estimates how much a solar hot water system would save and cost for your home. Right now it takes into account the recently improved 30% federal tax credit for SHW systems, but not your local or state incentives (we’ll be adding those soon). Our friends at Green Made Simple have an up-to-date listing of renewable energy incentives near you.

This project has also been built so that it is a special “cumulative” project, which means that the project details change as you select other projects on the list. Why is this useful? Because it can help you understand how much LESS you have to spend on a solar hot water system if you make less expensive upgrades such as installing low-flow showerheads or buying an Energy Star clotheswasher first.

As an example, the calculator shows that a solar hot water system would cost about $4,900 (payback period of 16 years) in our home assuming no water fixture improvements – pretty ugly! But if I check off the “low-flow showerheads” and “sink aerators” projects, the cost goes down to $2,500 (payback of 10 years). Our $40 worth of showerheads and $5 worth of sink aerators cut the estimated cost of a system by $2,400 by reducing our system size by one panel and reducing the storage tank size. By the way, the solar PV, graywater and total carbon offset projects work in the same way – they adjust each time you select a project that reduces electricity, wastewater or your carbon footprint respectively.

Last, we’ve made some additional improvements “under the hood.” One that you might notice is that we’ve modified the calculator so that you can’t enter overlapping projects. For example, once you select any one of the water heater insulation, tankless hot water heater, high efficiency hot water heater or solar hot water heater projects, the other three projects will be deactivated. This eliminates the double-counting that was possible by selecting overlapping projects before.

We’ll be making other additions soon (including wind power and using wood as heating fuel), so check back soon!

(Note: Our calculator is meant to be a preliminary planning tool for your green improvements. Before starting any of the more expensive projects, make sure you get a detailed estimate from your local green service providers … which you can easily find using LIL’s green services directory).

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