Tweet
Here is my turnkey 15 KW grid tied (net metered) solar array. An
NABCEP licensed local did the job in a few weeks. The annual
output is expected to exceed 23,000 KWH. For perspective, my
1977 Olds 88 is in the picture. The array is out of sight of my house,
the neighbors, or the road. It is 200' to the nearest out building,
and another 300' to the house.
I have already gone through the wiring loss calculations. With my
very long runs, DC losses peak at 1.4%. Even with oversize AC
wire, AC loses could reach 3.3% around the 604' loop. But I have
a total of 18 KW of panels feeding a pair of 7.5 KW of inverters, so a
7.5 KW peak OUTPUT is actually possible for each inverter despite
DC and inverter losses. And output will come up 20% on less than
ideal sun times. That is a lot of the time, here.
Coming alive just before solar noon, a lot of power was immediately
generated. For the half day saw 63 KWH, and the peak power was
14.93 KW at the AC line terminals. With that kind of daily sun, could
make over 40,000 KWH a year; never happen here.
After much studying the FORUM, I concluded this was about my
best bang for the buck, following local rules. I also noted that rules
vary widely from place to place; this meets all the LOCAL REGs,
inspections, & all the things I was looking for. Every last permit &
ground clip is in place.
The primary goal is to eliminate home energy purchases from the
electric & propane companies. The size is sort of fitted into the
available space (only cut 2 trees). Since payback wasn't a serious
consideration, some may choose to call it a SCIENCE PROJECT.
However its less than $1.60 a watt after incentives; with the low
maintenance of a PV system, it should add as much to the property
value. Really, the turnkey price is only about double the price of
just the panels. This would have been a lot more expensive a short
time ago.
My annual 5,000 KWH electric bill will be cancelled out. I'm adding
another R50 to the simple 6" ceiling insulation, hoping the annual
propane use might be reduced from 1050 gallons to 700 gallons,
or 18,810 KWH. I am a little short trying to replace that with
resistance heat. A year will get actual experience numbers, filling
any gap with propane.
If the gap is wide, a GEO THERMAL HEAT PUMP may be considered
to zero out ALL my home energy purchases. The propane equipment
will still in place as backup. If the power co goes out, a 4 KVA
generator will run the propane furnace (same as before).
The 1978 house was originally built as "all electric", and all the
original wiring and junction boxes are still in place. Looks like its
going back to all electric.
Bruce Roe
NABCEP licensed local did the job in a few weeks. The annual
output is expected to exceed 23,000 KWH. For perspective, my
1977 Olds 88 is in the picture. The array is out of sight of my house,
the neighbors, or the road. It is 200' to the nearest out building,
and another 300' to the house.
I have already gone through the wiring loss calculations. With my
very long runs, DC losses peak at 1.4%. Even with oversize AC
wire, AC loses could reach 3.3% around the 604' loop. But I have
a total of 18 KW of panels feeding a pair of 7.5 KW of inverters, so a
7.5 KW peak OUTPUT is actually possible for each inverter despite
DC and inverter losses. And output will come up 20% on less than
ideal sun times. That is a lot of the time, here.
Coming alive just before solar noon, a lot of power was immediately
generated. For the half day saw 63 KWH, and the peak power was
14.93 KW at the AC line terminals. With that kind of daily sun, could
make over 40,000 KWH a year; never happen here.
After much studying the FORUM, I concluded this was about my
best bang for the buck, following local rules. I also noted that rules
vary widely from place to place; this meets all the LOCAL REGs,
inspections, & all the things I was looking for. Every last permit &
ground clip is in place.
The primary goal is to eliminate home energy purchases from the
electric & propane companies. The size is sort of fitted into the
available space (only cut 2 trees). Since payback wasn't a serious
consideration, some may choose to call it a SCIENCE PROJECT.
However its less than $1.60 a watt after incentives; with the low
maintenance of a PV system, it should add as much to the property
value. Really, the turnkey price is only about double the price of
just the panels. This would have been a lot more expensive a short
time ago.
My annual 5,000 KWH electric bill will be cancelled out. I'm adding
another R50 to the simple 6" ceiling insulation, hoping the annual
propane use might be reduced from 1050 gallons to 700 gallons,
or 18,810 KWH. I am a little short trying to replace that with
resistance heat. A year will get actual experience numbers, filling
any gap with propane.
If the gap is wide, a GEO THERMAL HEAT PUMP may be considered
to zero out ALL my home energy purchases. The propane equipment
will still in place as backup. If the power co goes out, a 4 KVA
generator will run the propane furnace (same as before).
The 1978 house was originally built as "all electric", and all the
original wiring and junction boxes are still in place. Looks like its
going back to all electric.
Bruce Roe
I wish I had that much room to work with. I'm glad you only had to lose 2 trees, we are going to have to cut down 7. They are 60+ foot tall spruce and blue spruce that were hit pretty hard with the drought last summer. The good news is that it opens up my options for a ground array.
Comment