Chris M.

I've had a Tesla Model S for a few months now. How much does it cost me to drive it each day? Electric vehicles are more efficient than gasoline vehicles. fueleconomy.gov says : " Electric vehicles  convert about 59%–62% of the electrical energy from the grid to power at the wheels—conventional  gasoline vehicles  only convert about 17%–21% of the energy stored in  gasoline  to power at the wheels." Given an electric vehicles (EVs) increased efficiency, current electric rates, and gasoline prices, are you saving money on a per-mile basis when driving an EV? Tesla provides a calculator on their website to help people estimate the cost and cost savings between electric and gasoline cars. Tesla's calculator says it would cost $3.41 for electricity and $7.52 for gasoline for my typical daily commute of about 84 miles round trip. The text at the bottom of the calculator explains the criteria used to calculate those two costs, an electric rate of $0....

Our electric provider here in North Reading, Reading Municipal Light Department (RMLD) (http://www.rmld.com/), offers time-of-use and net metering as two alternative electricity tariffs to the standard flat rate. If your electric provider has these two options, how could you determine if either or both of these options would reduce your electric bill? Net metering is typically used by people that are generating as well as consuming electricity, for instance if you had a solar photovoltaic system. If you had solar you would very likely already have net metering, without a meter that supported net metering your solar system could be generating power and you wouldn't receive any credit for it. Time-of-use (TOU) tariffs vary electric rates based on time of day. TOU rates are commonly used by electric companies to help shape electric demand by increasing the cost of electricity during some periods and discounting it during others. Discounts for off-peak usage can result in the move...

A high level of humidity in your bathroom can result in mildew growth on paint and other surfaces. Many bathrooms have vent fans, some will sense humidity and will automatically run until the humidity level drops. If you have a manually switched vent fan you may find yourself forgetting to turn it on. If you remember to turn the fan on you might forget to turn it back off. We would often forget to turn the fan on until after showering and end up turning it off too early to avoid leaving it on when we went to do something else. Then I found an vent fan replacement switch like this: This is the  Leviton Humidity sensor and fan control  found on Amazon for $25. The Home Depot by our house also carries similar humidity sensors. The few sensors I've looked at appear to work similarly. They detect humidity and automatically run for some amount of time after the humidity level falls. The bottom part of the sensor is a button that you can press to turn the fan on and...

Karma automotive is making its second entrance into the automobile market, officially debuting the Revero in a couple weeks time. Summary Marketing and selling the Revero is going to be tough given the quality, performance, and features of cars on the market today. Given this competition I'm surprised Karma automotive has received funding to continue development of the Fisker Karma , now renamed to the Revero. I'll present a few reasons why the Karma Revero isn't likely to make a noticeable impact on the automotive market as well as some ways they can improve their chances by making changes to the Revero. Note that the Revero's full specifications haven't been released yet. For the purposes of this analysis I'll assume the Revero is more similar to the Fisker Karma than not. The Revero is likely to improve upon these specifications but from what information has been released about the Revero it doesn't appear that these changes will significantly c...

I recently installed a Neurio whole house energy monitor. Let's use it to see if we should replace some incandescent lights with leds. Neurio has a web interface and a mobile app that you can use to look at real-time and historic energy usage. Here are the lights in our living room. One light, seen in the lower right, was burnt out when we moved into the house earlier this year. To measure the consumption of the lights I got a baseline on the mobile app with the lights turned off, and then turned them on, 1,132 watts - 826 watts = 306 watts 306 watts / 5 lights = 61.2 watts per light This matches pretty closely with the 65 watt consumption label on one of the lights I checked. Neurio also provides the cost per hour of your current energy consumption, based on the electric rate that you enter when configuring your account. From the two energy graphs you can calculate that it costs $0.05/hr to run the lights in our livi...

You may have seen a few stories about the Karma Revero 's solar roof. For those that follow cars, the Revero is the re-born Fisker Karma , a hybrid gas and electric vehicle. By Fisker at speed in the fog.jpg: Fisker Auto derivative work: Mariordo (Mario Roberto Durán Ortiz) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons Fisker went bankrupt and was bought by a Chinese automotive components company. Fisker was renamed to Karma and the car was renamed from the Karma to the Revero. Karma's website has this text on their website about the solar roof : "Our solar roof will create enough energy to power the car. No other vehicle sold in the U.S. has ever offered this capability. Our owners consider our solar roof an important element in our brand identity, and we listened." Lots of sites have written stories about the solar roof idea, copying the information from Karma without doing any kind of analysis. Solar panels can ...

We had a garden a few years ago but didn't keep it up in 2014 or 2015. We moved to North Reading, MA in March and I finally made some time to setup a new garden. It's great having fresh home grown vegetables and I'm excited to get started growing them. With the help of my assistant it took about two hours to cut the wood sides of the garden box, set them up, level them, stake them, and fill the box with soil. It's a bit late in the season to plant but at the least the garden box is ready for next year. I planted some peas, beets, peppers, and basil and it seems likely we'll get some small amount of production this year. Figuring out the garden dimensions, trimming boards and leveling them Building some stakes to hold the pine boards in position. My assistant taking a break after working hard Some water and ice cubes to keep cool Leveling the soil. Look at the cute little fence to keep the dogs out Transplanted the Zucchini I start...