SERVICES:   ENGINEERING PROTOTYPES

 ENGINEERING ARTWORKS

  SITE MAP SUSTAINABLE LIVING
PRODUCTS:  LEVITATION KIT

 FURNITURE

  ELECTRONIC ARTWORK  THERMAL WINDOWS
SOLAR INFO: SOLAR POWER SOLAR HEATING SOLAR HOT WATER SOLAR MOWER
RESOURCES:  ABOUT ME  IN THE MEDIA  BUILDING A CANOE LINKS
CONTACT

home > solar power
Installing a grid intertied
solar electric power system


Overview System
sizing		 Financing Panel
Siting 		Hardware Grounding Rail
Installation		 Inverter
Installation		 Panel
Installation		 Real-time
Stats		 More
details
REAL TIME STATS
web cam view of workshop updates hourly on the hour during daylight hours
The image above is updated every minute during daylight hours,
the last image of the evening is retained over night, it is now:

Local weather:
ESTIMATED vs ACTUAL STATS
The chart below compares the estimated power that my solar panels should generate based on calculations from the PVwatts calculator provided by the National Renewable Energy Labs.  The actual energy produced is obtained from monthly reports provided by the Enphase Enlighten web interface (below).  The electricity that we purchase from the utility is shown in blue. 

Our usage varies a lot due to variations in our business use of energy intensive tools, lighting and computers.  Note for instance that June of last year shows a significant energy drop while my wife was out of town for 3 weeks.  Her business Younger Knits uses a 1.5kW  clothing steamer many hours a day and a lot of rinse water that involves the 1.5kW well pump and sump pump etc.  Energy consumption also peaks in the winter when we use small electric heaters to supplement our propane and wood stoves when outside temperatures stay below 20F for weeks.

I update the graph in the first week of each month to reflect the most recent month's data.

Notes:
January 2010 is high because we used small electric heaters in closed rooms a lot.
February 2010 is low due to a 3 day power outage that shut down the inverters.
 

Near real time performance data is below. 
On average we use about 15-21kWh/day.  This powers our home and 2 home based businesses with all the computers and relevant equipment.  For reference, average US homes consume upwards of 25 kWh/day.  If we were to eliminate all the business usage I believe we would average below 13kWh/day.

The design goal of the system is to generate a slight surplus in June/July and generate about 25% of our needs in the middle of winter.  Our 21 - 175 Watt panels produce 3.6kW of power in theory, but that ideal performance is derated by a factor of .87 due to various performance and efficiency issues so the actual peak power is 3.13kW.  As I observe the overall power over months, the seasonal variation of available sun hours becomes quite clear (see Lifetime Energy below).

I am experimenting with Google's powermeter web portal that shows electrical energy that we use.  I purchased a TED500 energy monitor and have connected it to the main power lines in the breaker panel that feeds both buildings and a second monitor is connected to our solar panels output.  So the combined information is shown below.  Since powermeter does not (yet) show negative values, you will see periods where the energy shows as zero - that is when sun is providing more power than we need and we are exporting it to the grid.

I am still debugging the system - so there may be some weird glitches in the graph that show up. 
Data tracking initialized on March 10, 2010 at 4:30pm.