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Hi to everyone. My name is Gord I am new, and would like to get a bit of advice regarding the best way to configure and how many panels you recommend, for my 250 ft run from panels to the charge controller, for an off grid system. I have a couple other questions I threw in as well. I will first apologize because I know I will get a bit wordy. I hope a few of you will read thru, and give me some layman advice. My reason for being wordy, is because I have read others give partial, incomplete info, that has resulted in various questions coming back at them.
This is a new 930 sq ft cabin/house at a 1/4 section of land in North central Alberta, latitude 54 degrees +-. Because it is new, everything is and will be high efficiency, including the wood stove. We have had this get away for many years, without the benefit of grid power, and don't plan to get on the grid now. By default we have become very good at conserving energy of all sorts. My wife and I have built 7 houses ourselves in the past, (when we were younger) and have learned how to source materials, and sub contractors. Before power it will be complete for about 1/3 of the price of hiring a builder, and everyone who worked on it left very happy. Our finances demanded that we do it ourselves.
For the next 6-7 years this will primarily be a 3 season retreat, when we have plenty of sun, with maybe a weekend or 2 each month in the winter. In 6-7 years our use will go up, and I will upgrade batteries, inverters etc as needed then. We have a very high efficiency wood stove for primary heat, and wood galore, We have most appliances, heat, and hot water on propane, we will be putting in a small electric fridge for occasional use, but have a propane fridge as well. I have roughed in everything from the hot water tank, furnace, and all appliances for both electricity, and gas. Every light installed is at or under 10 watts. Our other electrical use will be very efficient. I have done a use calculation numerous times, and we will be under 5000 watt hrs per day during heavy use, which wont be daily.
A bit about my install.
1) I have a good friend who is an electrician, who has worked industrial, commercial, and residential. He has done a few off grid residential installs in the past, and will install mine. He took a solar workshop, a few years back, to do remote stuff for the company he works for. Someone else designs, then he installs. He does not want to determine, my component needs, but will make sure the small details including remote, and onsite monitoring etc will be done correctly. I think that's fair. If I'm going to have the system I should learn some and continue to learn about it. I could press him but won't, he works enormous hours over the winter, in camps and such, then takes lot's of time of in the nice weather months up here.
2) I have a 300 ft length of 6 awg underground cable that I would like to use. I bought it as new scrap for $100 from one of the projects my friend was working on. I was hoping to get 4 awg but I couldn't pass this up. I am hoping done properly I can make this work. I have gone online and learned some about resistance. My real required length is about 235 ft end to end, but I am using 250 ft for a base length. The reason for the long run is to prevent shading from trees, to have panels and expansion without cluttering near the cabin. We also get direct south exposure, with a big snow cover field to help with reflection in the winter. This is the closest suitable spot.
3) I can get what I think is a good price on 10 new, Canadian Solar KuDymond 340 watt poly panels @ 50 cents a watt, 35 cents US bucks, I am unfamiliar with these split panels, but am hoping I can use these to start then add to later if or when we need. 340 watt, VMP 38.4 volts, IMP 8,86 amps. I'm pretty confident that wiring everything in series would work with 6 awg very easily, but don't think the charge controller will like it much. I am not too concerned about a little extra or less wire, my buddy gets it cheap, and he is installing for free. Him and a couple other friends use the place too. It's great for all of us. Greater security, and they help out, whether we are there or not. I do wonder if tigo optimizer will help with partial shade from clouds, and if they are worth the extra $500 or so they would cost me?
4) I can also buy good quality lead carbon 12 volt 200 or 250 ah batteries, at cost from the company my friend works for. (His brother in law is an electrical engineer, and very senior person at the company) They use a lot of batteries for remote monitoring, rail, and mining, etc. I am thinking about starting with 4-12v-250 ah batteries, and think I can keep them down to 50 to 60% DOD, or under for most use. The cycle life, and cold weather suitability, along with cost in a no maintenance battery is directing me to these. I also think that in the next few years companies like Nant and others are going to bring battery prices down, and longevity up. If nothing else I will up grade my complete battery bank with lead carbon down the road.
5) We are going to have a back up propane generator. I have a little 3000 honda that supplied all the power to build the cabin, and for our use to date, it will handle tools, and may handle back up if I convert it to propane, and can make it work with a back up switch.
It appears that the money we can save vs retail on cable/wire, panels, batteries, and install will put us in a decent up front cost position. I think I can save on racking, and maybe other components too.
Again I apologize for all the words. Here are my questions.
a) can someone please help me configure the above mentioned panels, and/or recommend others? to work with the 48v 250 ah battery. From late spring to early fall, I'm not overly concerned, but from late fall to early spring I am due, to our big decrease in sun hours. I want to configure with a focus on the lower winter hours, while using the backup gen in a less is better fashion. I just can't wrap my head around configuring the volts and amps in order to both run 250 ft, and charge the battery as quick as possible.
b) can I use a morning star/tristar 60 amp charge controller? If not please recommend other then midnight solar.
c) will this work with a 48 v 4000 inverter or less? We expect to go bigger when we retire. I may be wrong but I have also read that inverters do not have the longevity of solar panels, so I prefer to not overbuild too much just yet.
I will source the components as cost effective as I can, and our ROI, is not the biggest concern right now, but it looks like it could be pretty good. Part time power for the next 6 to 7 years is the priority. The power company quoted us $32,000 to hook us up, 3 years ago it was $17,000, which I thought was ridiculous then for the same thing. They obviously don't care about normal inflation. Then approx $125 per month in various service charges before using any power, which goes up every year. $9000 + in the next 6 years, before we even turn on a light bulb. $12,000 to $15,000, is more likely with power use. The price of power is also going up considerably year over year. Bare bones $44,000 in the next six years, then I'm very sure $3000 bare minimum to who knows what, every year after. $100,000 for power for 20 years use is very possible. I know I can do better. The technology, and I think the prices for solar will be better and more cost effective, in the years to come. The grid is not an option, we won't do it.
Thanks for reading, I hope some of you with knowledge chime in.
Gord
This is a new 930 sq ft cabin/house at a 1/4 section of land in North central Alberta, latitude 54 degrees +-. Because it is new, everything is and will be high efficiency, including the wood stove. We have had this get away for many years, without the benefit of grid power, and don't plan to get on the grid now. By default we have become very good at conserving energy of all sorts. My wife and I have built 7 houses ourselves in the past, (when we were younger) and have learned how to source materials, and sub contractors. Before power it will be complete for about 1/3 of the price of hiring a builder, and everyone who worked on it left very happy. Our finances demanded that we do it ourselves.
For the next 6-7 years this will primarily be a 3 season retreat, when we have plenty of sun, with maybe a weekend or 2 each month in the winter. In 6-7 years our use will go up, and I will upgrade batteries, inverters etc as needed then. We have a very high efficiency wood stove for primary heat, and wood galore, We have most appliances, heat, and hot water on propane, we will be putting in a small electric fridge for occasional use, but have a propane fridge as well. I have roughed in everything from the hot water tank, furnace, and all appliances for both electricity, and gas. Every light installed is at or under 10 watts. Our other electrical use will be very efficient. I have done a use calculation numerous times, and we will be under 5000 watt hrs per day during heavy use, which wont be daily.
A bit about my install.
1) I have a good friend who is an electrician, who has worked industrial, commercial, and residential. He has done a few off grid residential installs in the past, and will install mine. He took a solar workshop, a few years back, to do remote stuff for the company he works for. Someone else designs, then he installs. He does not want to determine, my component needs, but will make sure the small details including remote, and onsite monitoring etc will be done correctly. I think that's fair. If I'm going to have the system I should learn some and continue to learn about it. I could press him but won't, he works enormous hours over the winter, in camps and such, then takes lot's of time of in the nice weather months up here.
2) I have a 300 ft length of 6 awg underground cable that I would like to use. I bought it as new scrap for $100 from one of the projects my friend was working on. I was hoping to get 4 awg but I couldn't pass this up. I am hoping done properly I can make this work. I have gone online and learned some about resistance. My real required length is about 235 ft end to end, but I am using 250 ft for a base length. The reason for the long run is to prevent shading from trees, to have panels and expansion without cluttering near the cabin. We also get direct south exposure, with a big snow cover field to help with reflection in the winter. This is the closest suitable spot.
3) I can get what I think is a good price on 10 new, Canadian Solar KuDymond 340 watt poly panels @ 50 cents a watt, 35 cents US bucks, I am unfamiliar with these split panels, but am hoping I can use these to start then add to later if or when we need. 340 watt, VMP 38.4 volts, IMP 8,86 amps. I'm pretty confident that wiring everything in series would work with 6 awg very easily, but don't think the charge controller will like it much. I am not too concerned about a little extra or less wire, my buddy gets it cheap, and he is installing for free. Him and a couple other friends use the place too. It's great for all of us. Greater security, and they help out, whether we are there or not. I do wonder if tigo optimizer will help with partial shade from clouds, and if they are worth the extra $500 or so they would cost me?
4) I can also buy good quality lead carbon 12 volt 200 or 250 ah batteries, at cost from the company my friend works for. (His brother in law is an electrical engineer, and very senior person at the company) They use a lot of batteries for remote monitoring, rail, and mining, etc. I am thinking about starting with 4-12v-250 ah batteries, and think I can keep them down to 50 to 60% DOD, or under for most use. The cycle life, and cold weather suitability, along with cost in a no maintenance battery is directing me to these. I also think that in the next few years companies like Nant and others are going to bring battery prices down, and longevity up. If nothing else I will up grade my complete battery bank with lead carbon down the road.
5) We are going to have a back up propane generator. I have a little 3000 honda that supplied all the power to build the cabin, and for our use to date, it will handle tools, and may handle back up if I convert it to propane, and can make it work with a back up switch.
It appears that the money we can save vs retail on cable/wire, panels, batteries, and install will put us in a decent up front cost position. I think I can save on racking, and maybe other components too.
Again I apologize for all the words. Here are my questions.
a) can someone please help me configure the above mentioned panels, and/or recommend others? to work with the 48v 250 ah battery. From late spring to early fall, I'm not overly concerned, but from late fall to early spring I am due, to our big decrease in sun hours. I want to configure with a focus on the lower winter hours, while using the backup gen in a less is better fashion. I just can't wrap my head around configuring the volts and amps in order to both run 250 ft, and charge the battery as quick as possible.
b) can I use a morning star/tristar 60 amp charge controller? If not please recommend other then midnight solar.
c) will this work with a 48 v 4000 inverter or less? We expect to go bigger when we retire. I may be wrong but I have also read that inverters do not have the longevity of solar panels, so I prefer to not overbuild too much just yet.
I will source the components as cost effective as I can, and our ROI, is not the biggest concern right now, but it looks like it could be pretty good. Part time power for the next 6 to 7 years is the priority. The power company quoted us $32,000 to hook us up, 3 years ago it was $17,000, which I thought was ridiculous then for the same thing. They obviously don't care about normal inflation. Then approx $125 per month in various service charges before using any power, which goes up every year. $9000 + in the next 6 years, before we even turn on a light bulb. $12,000 to $15,000, is more likely with power use. The price of power is also going up considerably year over year. Bare bones $44,000 in the next six years, then I'm very sure $3000 bare minimum to who knows what, every year after. $100,000 for power for 20 years use is very possible. I know I can do better. The technology, and I think the prices for solar will be better and more cost effective, in the years to come. The grid is not an option, we won't do it.
Thanks for reading, I hope some of you with knowledge chime in.
Gord
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