Friday, June 12, 2020

Electric Mower - 'tis the season


My wife had the inspiration more than 10-years ago to buy an electric mower.  I think she was tired of dealing with gasoline and wanted a cleaner option for cutting the lawn.  It was a great move!

We've got a battery powered Toro.  I don't believe the model is offered any longer, but lighter/newer models are available from other manufacturers including greenworks, Makita, Stihl and others. 

Our mower is built around a 36V motor that relies on three lead-acid AGM batteries.  The mower is a bear to push owing to its weight.  I've been looking for a lithium replacement battery to help reduce the weight, but haven't found anything suitable as of yet.

Every cordless mower that I currently see on the market is powered by a lithium battery.  They are lighter and speaking generally are superior to their combustion counterparts in several other ways too.  They are:

Quieter
Easeir to start (no choke, no pull cord)
Easier to maintain (no gas, no oil, no carburetor, no spark plug, no winterization)

and they can be powered by cleanly produced electrons from the solar on our roof!


Here's a short video segment that shows the ease of starting and stopping the mower.









Tuesday, May 19, 2020

Off-grid Solar and Radiant In-floor Heating



This is a home that I installed an off-grid power system at near Elkins, WV.  I was "in the neighborhood" on Sunday and took a couple of snaps.
Red Creek Construction built the home in 2018/19.  It's a story-and-a-half on top of a full basement.  The electronics and batteries are in the basement.  Having adequate mechanical space for batteries and electronics is very important with an off-grid system.  This particular system uses most of a 8' X 12' room.

The solar PV array on the roof was sized to power the home with little or no assistance from the Kohler 14K generator.  There are twenty-three 295-watt SolarWorld PV modules.



The house has in-floor radiant heating and a deep deep well.  While the radiant system uses a LP boiler to heat the water it is also dependent on a series of electric pumps to circulate the water to the different heating zones.  The individual pumps are small in terms of their power draw, but the combined use of all the pumps running throughout a winter day can add up to a significant electrical load.  On similar homes with in-floor heat the daily energy consumption in the winter can be double what it is in the summer months.

Here the solar is sized to handle the full load in winter when heating demand is at its peak and solar exposure is at a minimum.  The upshot is that the shoulder and summer months enjoy an excess of energy production and the homeowners report that it is not uncommon for the battery bank to be fully re-charged before noon.



Monday, April 27, 2020

Electric Greg - Movie Short for Those Curious About Electric Cars




My couty's development director turned me on to a short film focused on one adventure athlete's personal challenge of transitioning to the exclusive use of an electric vehicle.  It's about 20 minutes in length and was a fun watch for our family.
 



Monday, April 13, 2020

Charging an Electric Vehicle with Solar - Pendleton County, WV


(Chevy Bolt EV getting a fill-up at home from a ClipperCreek Level II Charger)

Electric Vehicle (EV) charging has a new boost from a re-instated tax incentive that offers a 30% federal tax credit to businesses and homeowners who install EV charging stations before December 31, 2020.

The tax credit legislation also retroactively applies to EV chargers installed in 2017, 2018 and 2019.  To read a bit more about the legislation and find the IRS form you can take a look at pluginamerica.org

Solar also continues to enjoy an exceptional tax credit through 2020 at a rate of 26% of the installed cost.

 

This particular solar installation powers the charging of a Chevy Bolt as well as the energy needs of the classic Sears kit home in the background.  The system is grid-tied for net-metering with  MonPower, the local utility.












Friday, February 14, 2020

Solar in the Woods -Grantsville, MD





This 4.32-kW solar PV system was installed in 2011.  At that time, an arc of trees had to be cleared away from the garage to ensure that the system would operate at its peak. The house has recently been for sale and the owners asked a friend to fly some drone imagery for the sale advertisement. 

The image below shows the extent to which the surrounding forest was cleared to allow for shade-free operation of the solar.  I think it's helpful to see this birds-eye view years later as it illustrates the cleared area, but also shows shadows from the trees that were left.



The garage is south facing and I'd expect the image was captured close to noon.  By providing a clear skyview for their solar panels these customers were able to meet their goal of making more electricity than they required.  They are moving to a new home built to a Passivhaus standard where they expect to also be net-zero.

Thursday, April 5, 2018

Still Hollow Spirits: Solar 'Shine

The Parsons Advocate ran a nice article this week about our local distillery, Still Hollow Spirits.  Based in Job, WV and taking advantage of an excellent spring water source, Still Hollow produced its first batch of corn whiskey just in time for the holiday season.  They rapidly sold out of batch #1.
stillhollow_owl
Construction of the distillery building included the installation of a 9.6-kW solar PV array.  After  a year of operation the solar has produced more energy than consumed by the distillery leaving Still Hollow with a net metering credit.  Clean energy, clean water and clean living!

https://stillhollowspirits.com/sustainability/
The solar PV array consists of thirty-two SolarWorld  300-watt modules (MADE IN THE USA!).  Two SMA SunnyBoy SB-series inverters are used to convert and connect the solar power to the utility grid.  The system is designed for net metering with MonPower.

Still Hollow Spirits is a really nice place to visit.  It is an easy drive from Seneca Rocks, Canaan Valley, Spruce Knob and Elkins, WV.  The distillery is open for tastings and tours.  The best place to get in touch and check on their hours is through their Facebook page.









Friday, March 23, 2018

Batteries in the Spotlight at 2018 Niagara NABCEP Solar Conference

 
Macrohydro

The number of battery vendors at this year's NABCEP solar professionals conference was noteworthy as was the introduction of Morningstar's soon to be released 48V battery-based 4K inverter lineup.  The emphasis on battery-based direct current systems was ironic, given the location was Niagara; well known as the place where modern utility-scale alternating current had its debut.  Mr. Edison would have been pleased.

One observation frequently made was that the solar industry, after years of being dominated by battery-less grid-interactive systems, is now seeing its future closely aligned to battery storage systems.

Sonnen 4-kW Battery System for Backup and Load Shaving (includes an 8-kW Outback Inverter)

Lithium battery manufacturers present included Hawaii's Blue Planet, Germany's Sonnen and Vancouver's Discover AES.  I am frequently asked about lithium alternatives to lead-acid batteries which have been the mainstay of off-grid and backup systems for years.  In short, the technology is here, but any adopter may be on the bleeding edge as systems have a steeper entry cost and an unproven track record. Could be good, though!

Something else that could be good is the new 4-kW 48V inverter from Morningstar.  This is a company that has built a really nice line of solar charge controllers over the last 25-years.  I've used their PWM and MPPT equipment on both solar and microhydro systems.  This is their first "whole-house" or big inverter.  Notable among the features include:
  • 18W idle loss (this is way low - like 47% lower than an Outback FXR unit)
  • 120V or 120/240V
  • Integrated control panel
  • Space for six relay blocks (ie, generator start, vent fan turn on, on/off loads, etc...)
  • No cooling fan
  • Dummy-proof bypass switch
  • Breaker panel for code compliant installations 

 Morningstar's 4-kW Inverter with the Covers Removed