September is upon us. Here in southwestern Ontario Canada fall is approaching fast. The additional panels were of great improvement especially for after 5:00 pm

This summer the mighty Geothermal heat-pump air conditioner was flexing its muscles using solar produced electricity. The addition of 3.5 kw helped with a state of charge that would have us cruise through the night in total comfort. If the morning greeted us with sunshine we are set for another day. However if the morning sun was a little shy we had to make the switch to grid for an hour or two until it was bright enough to gain us some electrons.

All in all many days would pass and the off grid smile was still present.

Today holiday Monday we sill have the switch off grid Charging the car, air-conditioning and washing clothes with fridges and coffee pot in operation

Additional batteries and a little wind are on the list as well as a little larger low pass filter for the inverter. During high energy uses it gets a little warmer than Id like but no smoke.

Its a win

Randen

Randen, I'm impressed that you made your own inverter! I would love to come by sometime for a peek at your systems since it is very encouraging what you have done.

About 3 1/2 years ago I had to pick up my son at someones place near Saranac, MI. For some reason, I went into the garage/shed and saw a huge board, about 4' x 6' full of light bulb bases. I asked if they were trying to provide a load on something, and was told that this gentleman's friend had designed (on kitchen napkins) and built an inverter that was 10K(?) watt. I was duly impressed! I never got back to that place, sadly enough, so, I don't know if there was more progress or anymore details.

Today a bit of an interesting event. But first a little history. Yesterday mostly sunny and a full pack at 7:00pm. Dinner was cooked on our electric stove top and a meatloaf in the oven again electric. A load of wash took place after followed by a half hour of tumble drying. I had mentioned to my significant other that we probably would not have enough power to dry the load completely. So she put the clothes on the drying rack to finish drying.

I have to encourage her to embrace the new solar power system to change habit and do high energy tasks during noon time. She has the habit of doing these tasks off peak with time of use grid costs.

Last night was uneventful and we coasted though the night off grid. The morning light (thin overcast) started the charge as usual we cooked breakfast and had showers all those menial morning tasks. At 10:30am the car is scheduled to start charging and thats when the clouds rolled in. About noon we had exceeded the batteries capacity and the system shut down.

No real problem the car has lots of charge, so stop the charge and the house battery recovered in 1/2 hr and we resumed the off grid life style.

As of about 6:00pm we have a full charge to do it all again.

High energy demands and irradiance conditions still can complicate things. But it sure beats a power bill!!!

I can see where a huge 85kwh battery would be nice!!!

Randen

Here in Southwestern Ontario Canada the energy company just announced costs increases. I understand that through regulatory bodies the prices are reviewed twice a year. This year a sizeable increase was pushed through.

The price for peak TOU went from $0.14 to $0.20 Ouch. 43% increase for the 1st of Nov.

We are Really pleased we don't feel the full force with this as we do spend most time off grid.
Although the winter months can be quite overcast and a lot of snow covering the panels

Randen

Randen,
See my latest post on a LiFeP04 backup battery bank in the "Solar Power" section
Rob

working toward off-grid
 

Fellow EcoRenovators

Winter has begun here in southwestern Ontario. Days of overcast and wind. The 14 kws of solar only produce on the average 15 kwhs of stored energy. So not near enough for operating consecutive days off grid.

The next facet was to investigate wind. I purchased a small turbine and have mounted it on a steel pole. I want to study this a little bit to possibly expand this in the coming summer.

We have built a voltage boost circuit to increase the wild AC output to 390 VDC to charge the lithium pack. Yet to design and incorporate a proper dump load and redundant charge controls.

Oh well I have the whole winter

Randen

This is an awesome post you share here. Thank you for sharing this blog with us.

Our farm in northern Maine sits on a ridge facing the west, and presumably has decent wind potential. I've often toyed with the idea of using one of those small turbines to tinker with. However, I may just set up one of my Davis weather rigs with an anemometer using an arduino or Raspberry Pi as a man in the middle to scrape data. The anemometer is just a series of contact closures per set period of time. This sort of remotely accessible data may prove useful to determine our potential wind feasibility.

Looking forward to your experiments Randen! :thumbup:

Anyone working to off grid
 

I had been interested in wind for a long time. I was very fortunate to have a close friend that had been in the business of manufacturing these for a short time. These 1-10kw turbines were used in remote areas and were plagued with maintenance issues. It was the day of lead acid batteries and lack of robust designs to keep the costs to a minimum. A proper tower and controls coupled with the cost of installations with proper footings made them quite expensive.

There are so many hurtles with wind. The first one is speed control in strong winds and even more so when the battery is full. To open the charge circuit when the battery is full can allow the turbine to run away with no load and one can expect a catastrophic failure with blades flying in any direction. The furling type is still dependant with having a constant load, however the turbine with pitch adjustable blades does not. Although more complex, for a larger turbine this is highly desirable. If the load is removed from the pitch adjustable turbine, the rpm doesn't increase.

Another factor is the wind is not kind to any dynamic machine. That large spinning propeller being spun this way and that are susceptible to some huge gyroscopic loads. Blades flexing and bearings in weather extremes don't make their expected life spans. The slip rings carrying the current from the alternator down the tower preventing the cable from twisting up, also has a hard life.

I had explored the thought of building an axial wound alternator large enough to power our home but the task is huge. A 5 kw alternator would be a sizeable machine with huge blades to carve and a tall robust tower. $$$$$ A concrete footing with a steel 50' tower, the costs would be prohibitive.

The wind resource is another part of the equation, little wind, no energy-simple enough. Here in southwestern Ontario the winter provides a decent amount of cold dense wind. The solar panels are covered with snow and that coupled with overcast and limited hours of daylight negates the energy equation. So bring on the wind.

The experiment with the 500w turbine is to check power/wind resource and resilience of a mono tower without guy wires. The pole is actually my sons basket ball pole. He won't be using it anytime soon so until then its on turbine duty. When I have some results and firm up plans I will elaborate with the group.

Enjoy Christmas Holidays

Randen

I did some research on wind but I am South Carolina and we don’t have good wind.
Luckily, we don’t have snow to cover our solar panels.

Good luck I will sit back and watch this one.

December 21 the day is sunny and no snow to speak of.!! This can change at a days notice. We are off grid and collecting electrons and heat from the solar hot water collectors. The home is heated with in floor heating and by default will take the solar hot water first and then backup with Geo-Thermal which will come into play when the sun is down and use the electrons we had collected from the PV.

However we are subjected to many days with overcast.!!! during winter.

The wind turbine has been working well however my wind resources have been a little shy.
My Mrs. has raised an eyebrow to the turbine as she likes all quiet when sleep is necessary.

The temporary location is quite close to the house but in a windy conditions you hear more noise in the trees and noises the house makes and none from the turbine. Thats a win!!!!

I will be marking a calendar to wind speeds and dates for production made. The turbine is more of a dynamic anemometer.


Anyway the best of the season

Randen

Randen - thanks!
I'm also at the point where I'm ready to install wind. I've been monitoring my Davis station for years now and I have enough good wind on my front acreage. Many years ago I bought a couple of those small South West turbines, about 400 watts each but you need really high winds to get that. I'm thinking if I can get 1/2 that it will be good enough to supplement my heat.
I'll keep an eye out for your findings.
Rob

We’ve worked hard to get off the grid. We have solar PV and air source heat pump. The ASHP was always the question mark in terms of effectiveness and performance. But we’re approaching the end of winter and the results have been interesting.

mrmhf

That is awesome you are off the grid. That's a huge accomplishment !!! Kudos.

I've temporarily installed a wind turbine to monitor the wind resource. I have to say I'm quite disappointed with the wind here in Ontario Canada

The weather has changed so much Feb. is so different now with temps of plus 0 deg.C for a high was unheard of. Today was 8 Deg. Nice because of all the sun which kept us off the grid for the day. But typically it would be snow cold and wind.

The overcast and lack of wind now is another spectical. Winters here typically the wind shook the house. Its been so calm.

We are still testing the boost inverter. 48 VDC to 390 VDC for the lithium pack charging.

Randen

Gathering wind data over a year or two is good insurance against failure. About 40 years ago someone in our community put up a wind generator based on anecdotal evidence that "wind is always blowing through that valley".

I drove by it every day for two years. Not one day in ten was it spinning. An ice storm finally put it out of it's misery. The owner wasted $10K.

The problem with many turbines from that era was that they wouldn't turn in anything less than 10MPH. Sailboat turbines still have this problem.

Anyone working to Off Grid
 

Its time to make a couple upgrades to the 20KW inverter. 2 items need some improvements:

The small pump motor thats being powered by PWM supervised by a thermistor in the liquid cooled heat sink needs a different method. Lower temperatures cause a PWM signal that makes the little pump motor squeal in a high pitch. Not cool!! at night to hear that squealing noise coming from the garage. I going to change that out for a simple snap switch to simply turn it on and off around 30 Deg C.

also another snap switch for over temp incase for some reason the pump becomes inoperative. 85 Deg.C

The choke coil although it didn't burn off its enamelled wire insulation during high current demands it did get hot. So its now re-wound with heavier gauge copper.

The inverter has been working extremely well !! The electric bill has proven that point. For the time its been off line and we resorted to buying for the grid OUCH.$$$ and its been hot! so the heat pump has been flexing its muscles

Randen

Try increasing the PWM frequency to above 20kHz.

NiHoaMike

The purpose of using PWM was to vary the speed of the pump to the heat load needing to be dissipated while prolonging the life of the little motor. As the thermistors temp was up and down so went the motors RPM.

Im just guessing, but I'm sure the motor was stopped but the low PWM caused a little squealing noise that was extremely irritating during the nite.

The snap switch is a simple device and should last a long time at the required current draw. The pump motor is near silent at the rated voltage and the intermitted duty will extend the life without the noise.!! Win-Win

Randen

That is not off grid. That is stealing power. There is a difference.

It's not stealing any more than charging a laptop or hybrid bicycle - there are power strips installed in the study areas specifically for that purpose. Keep in mind that the size of the battery is limited by how much weight can be easily carried, so probably 1 or 2 kWh would be the limit.

That was about 10 years ago and a lot has changed with the economics of doing that. Batteries have gotten a lot cheaper and LED lighting even more so. But I also have no idea how the service charges have changed in the area.

off grid is something that I would love to do. However, I dont think I could ever do it, as I have a large family. Maybe I could get my consumption down a bit though

Off grid is not ideal if you don't have to. The best solution is to have an intertie/backup system where the batteries are kept charged by the grid and they don't cycle up and down on a daily basis. Batteries are rated on cycles, how often they get charged and discharged.The intertie sells your excess back to the grid, it's really the best solution.

When the grid goes down you have battery backup and when the grid is up you sell your excess production back to the grid.

This way your batteries last much longer and you still get a benefit from your system.

Good quality batteries are rated to last thousands of complete cycles nowadays, even more for partial cycles. If you don't use them, they'll eventually die of old age.

Selling to the grid is not a good option in some places.

The best current battery for backup is LiFePo4. They generally last about 2k to 2.5k cycles. If you cycle those batteries 50% everyday they will last ~7 years. It's your choice but they are expensive.

If you sell everything back to the grid after all your own demands are met you will effectively be using the grid in place of your batteries for decades. Think about it, your PV still runs your house but your batteries aren't taxed until the need arises.(grid failures)

The only time complete off grid works is if you live so far from the grid that you can't get grid power or that the expense to bring grid power to your house is extremely costly.

Or

The Grid will not allow a connection. I had applied 3 times with descending solar outputs 10kw, 6kw, and 2kw

Sorry in-eligible!! due to power constraints. Micro fit or net meter. DENIED

Randen

The grid or your provider? Is it a technical problem or a political one?

Robaroni

Its my electric supplier (Hydro-one) and political. The supplier is claiming too many Micro-fit programs with cause an unsafe condition for the power lines. You and I both know that 10 Kw will be used by myself and my neighbour without any problem with the grid. To them its lost revenue

Randen

They're just trying to slow down the inevitable. Renewables are the future, now I'm seeing pros going to fully electric yard maintenance equipment and major auto manufacturers like VW and GM, that just merged with Honda, going full bore EV's. The fossil fuel industry is dying and like coal there's nothing the industry can do about it.
The halcyon days of the Koch's making 9 billion a year is coming to an end, the scale is tipping.

Raden, I've had the opposite problem. The power company sent a spotter out to decide where to put the poles and saw my solar panels. He told me they can't make any money selling me electricity. That's with me buying the poles, transformer and wire!
The moral: If you have solar, hide it until you get grid power.

I find it interesting on youtube. People installing a few solar panels with a couple lead acid batteries and a small inverter to start with and intending to grow the system. Ultimately becoming dis-satisfied with the small systems performance and there goes the dream.

I followed a youtube couple with the desire to build off grid. I think I had seen only 6 panels. and the lead acid batteries that were used, so absolutely on there last legs. So he was trying to run power tools and a small trailer that they had lived in while building.

He had become quite disappointed with the system.

Had he installed 10 kw solar or more with lithium tech and some proper inverters. He would have been a lot happier!! For back-up a proper generator possibly propane. He would have avoided the cost for a power line from the grid to his build which cost him huge.

Randen