REAL TIME STATS
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, averaging about 53% of our needs annually.
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). |
Local Time:
Current local conditions:
Web cam updates every minute:
refresh your browser to see the most current image
|
ESTIMATED vs ACTUAL STATS |
The
chart below shows 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 (above).
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 the first day of each month to
reflect the most recent utility and solar data.
(I have also been tweaking the graph to make it more readable
- just added the Solar EXPORTED line in August 2010)
Notes:
|
January 2010 |
Energy usage high because we used small electric heaters
in closed rooms a lot. |
|
February 2010 |
This month is low overall due to a 3 day power outage that shut
down the inverters. |
|
March 2010 |
Record rainfall created a lot of overcast days -
reducing production. |
|
May 2010 |
May was a very dry, sunny month this year. |
|
June 2010 |
Very cloudy + rainy, probably would
have had an energy surplus with clearer skies. |
|
July 2010 |
Hot and humid - using small air conditioner +
dehumidifier. |
| August 6, 2010 |
Added 2 more panels = 350 more
Watts! Away for 7 days so used less power. |
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