Renewable energy system update! The new monitoring system is up and running. We can control whether the inverter is on or off. At present, we can turn the inverter off on demand and it will automatically turn the power back on when the battery bank is nearly depleted. We now need to look into extending this time period by using a separate battery bank and small inverter. Being able to control the inverter electronically is a big step forward.
The next piece is adding more logic to the system. A piece of critical logic is to have the system turn the inverter back on when it detects that the temperature of the house reaches a critical level. The (below) graphic shows a green line that is closer to ZERO amps. Instead of burning 4 to 6 amps continuously, we can make the system idle so it is only using 0.3 to 0.5 amps.
Using the ability to turn the system off, it looks like we can go to running the generator every third day instead of every second day. Say, we need to run the generator from Oct to Feb (appox. 151 days). Every 2nd day would be 75 generator runs times 10 run hours or 750 engine hours. Every third day is 50 generator runs or 500 engine hours. Good deal!
Here is a curious device for those with wood stoves and are off grid. How about powering some lights from your wood stove? Up to 13.9V at 30 Watts? I've not tested this yet, but here is a link:
http://www.tegpower.com/pro1.htm.
Friday, December 2, 2011
Wednesday, November 16, 2011
Home again
We spent a fabulous week in Florida, working on Tai Chi (we aren't skilled enough for it to be all play). We met the instructor in the Atlanta airport on the way there - she recognized our T-shirts - she came down from Toronto. But now we're back. Here are some tracks we made coming home Tuesday morning (2 AM):

Note that the bottom of the car was acting as something of a snow plow.
Here's Rob doing some brushing:

Can you see the two orange flags? Any guess as to what they mark?

That's right - beyond them is the drop-off. If you step out there, you'll sink to your knees and beyond.
Here's Rob adding some finishing touches to the shoveling:

Ester Dome from the top of our driveway:
Note that the bottom of the car was acting as something of a snow plow.
Here's Rob doing some brushing:
Can you see the two orange flags? Any guess as to what they mark?
That's right - beyond them is the drop-off. If you step out there, you'll sink to your knees and beyond.
Here's Rob adding some finishing touches to the shoveling:
Ester Dome from the top of our driveway:
Sunday, November 6, 2011
Just a tiny bit of sun at sunrise this morning. It won't be long until it stays below that ridge on the right all day long:

I know this blog is pretty quiet. I've been posting more often over here.
I know this blog is pretty quiet. I've been posting more often over here.
Tuesday, November 1, 2011
Wednesday, October 19, 2011
Bunny Sitting
Some fun bunny sitting for a neighbor. Just try to switch their water bottles out...
Bunny & Waterbowl...
Bunny & Waterbowl...
Tuesday, October 4, 2011
GVEA Rates @ 96W: Do the math
Fairbanks, Alaska GVEA Rates as of 09/01/2011:
Each meter: $17.50/month
Utility charge: $0.08791/kWh/month
Fuel charge: $0.10924/kWh/month
Regulatory: $0.000492/kWh/month
What is the cost if you left a 96W light bulb on all the time?
First, calculate the kWh for the month, lets say 30 days on average.
30 days X 24 hours = 720 hours/month
720 hours X 96 Watts = 69120 Watt hours (Wh)
1000 W in 1 kW ==> 69.120 kWh of power used per month
Now multiply 69.12 kWh against the rates to get the cost of running 96W all day for a 30 day month:
For simplicity, we add all the rates up: $0.20207/kWh
69.12 kWh X $0.20207/kWh = $13.97 per month in power & regulatory fees.
With the meter charge, your nearly 100W light bulb is costing you $31.47 per month (or $377.64 per year). That is some expensive light bulb! No wonder they give out light bulbs for free at the annual meeting.
What things do you leave on all day?
Each meter: $17.50/month
Utility charge: $0.08791/kWh/month
Fuel charge: $0.10924/kWh/month
Regulatory: $0.000492/kWh/month
What is the cost if you left a 96W light bulb on all the time?
First, calculate the kWh for the month, lets say 30 days on average.
30 days X 24 hours = 720 hours/month
720 hours X 96 Watts = 69120 Watt hours (Wh)
1000 W in 1 kW ==> 69.120 kWh of power used per month
Now multiply 69.12 kWh against the rates to get the cost of running 96W all day for a 30 day month:
For simplicity, we add all the rates up: $0.20207/kWh
69.12 kWh X $0.20207/kWh = $13.97 per month in power & regulatory fees.
With the meter charge, your nearly 100W light bulb is costing you $31.47 per month (or $377.64 per year). That is some expensive light bulb! No wonder they give out light bulbs for free at the annual meeting.
What things do you leave on all day?
Thursday, September 29, 2011
What is left to save?

Here is an example. The power we are trying to save is the amps along the green line. During the day the system is consuming an average 4 amps. The higher spikes is the oil heater making hot water. If the system was turned off during idle periods, we could be conserving amp hours to stretch into our third day.
Additional note:
4 amps? This isn't 4 amps at 120V but 24V. Our phantom load is 96W or less than 1 amp at 120V (roughly 0.8 amps at 120V). So, at idle times we have a 100W light bulb on all the time. If we shut the house down, the inverter will consume much less.
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