@11:50 Watching the power output go from 170 to 238 watts. It still surprises me how much power a little bit of shade can cost you. I noticed the same thing when I initially had my roof mounted panels under the roof rack. I could see this mounting method being very popular in Alaska or northern Russia though. It is very fascinating to consider how solar cars will adopt different necessary adaptations at different latitudes. Also I laughed me ass off at 16.19
The shadows of the struts / stays could be affecting your solar collection too, even a little bit of shading can limit the current from the whole string (of cells) AIUI. So this is with your custom DC-DC converter again, it's been a few months since the last person asked so I will do it, how is that coming along? I gave up on his route because I want to be able to charge the battery to full, and get the OBC / BMS to do its balancing normally, also I'm too scared to mess up the BMS / required charging profile / destroy the wiring. My car only top balances and if it never gets there... that wouldn't be good. But mainly because I don't know how to make a DC-DC converter myself! 😛 I spent a long time looking into using the DC "fast" charge port, but the protocol is a nightmarish superposition of powerline comms, TCP/IP, home automation, XML (including auth!), TLS with private certs and after all that they end up with a one-way client-server protocol, atrocious. The losses with AC can be kept under control and with the EVSE you can even charge a friend's car if needed.
Your channel is very interesting, I’ve owned a 2012 Chevy volt for many years now and I love the car but with our Canadian winters the range drops to less than half. I end up burning just as much gas as a gas powered economy vehicle in the winter. I’m would be interested in perhaps adding an extra battery pack to charge when I’m parked using direct dc-dc charger or just simply tying the extra battery in in parallel, have you seen this or something similar done on a volt? I have access to almost limitless cheap lithium ion 18650 cells that could be used to make a pack with even more capacity the the original volts battery but don’t want to add too much weight. I’m considering eliminating the back seat for the extra battery rack since I never use it.
I finally got to test a Volt in cold weather. Ouch! The battery greyed out and the engine ran. Guess this was due to a cold battery. It was different than "Engine Running due to Temperature" which is caused by air temperature. The Volt expends a substantial amount of energy heating the battery. Maybe it would help to better insulate the battery and add an external battery heating pad. It could work like the Electrodacus system, splitting solar (or battery) energy between battery heating and battery charging. My DC-DC could charge from a battery instead of solar. But with an output of about 500w it may not be enough to make a big difference. If a DC-DC could supply 2kw when the car was on, that would counteract the power used by the battery heater. www.enginer.us/ has a 5kw DC-DC. A big problem with an add-on DC-DC is that it won't heat a very cold battery before charging. My DC-DC would check battery temperature first, but it doesn't control the OEM heater. If the power was ran through the J1772 port all of the factory battery heating logic would still operate. I have confirmed that the Volt will charge from 120v DC. But when I tested it I couldn't get over 6 amps. That may have been due to the battery internal resistance.
@@realsolarcars Yes, I did give some thought about adding a coolant heater in the battery coolant circuit to preheat my battery a perhaps run it on a battery when driving in cold weather to keep the battery warm. I recently removed my battery to replace the OEM heater for a unrelated issue but I decided to relocate it behind the engine for easy access for further experiments. I will post a video on my channel when I finally get the added heater installed. Cheers
How's the DC-DC converter going? Is the new board working well? I'm coming around to the idea that this is the only way to go now. The losses I'm seeing in my testing with solar array->MPPT->buffer battery->inverter->OBC->traction battery are just too high, and the OBC is the worst culprit. For those with CCS (like me) I now think it wouldn't be too hard to add a DC EVSE, could use one of the SoCs (found a couple for under $20) that implement the GreenPHY powerline comms.
The new boards were running too hot. A revised version was a lot better but still ran hotter than the original 2019 version. We felt it best to redo again to try and drop the temperatures some more. If all goes well they'll be available by June. It seems like we had a generous amount of beginner's luck on the first board. Being new to power design it's hard to know just how hot parts can run reliably. There were also issues like EMI and ringing that we just ignored on the first board. Considering how most tests went we thought for sure that there would be some issue with the car throwing a fit about our DC charger. Now we will use the charger while driving as well so it would be good to not loose radio reception to interference. The panel frames literally touch the antenna. Charging while driving add its own issue with ripple on the battery that we haven't tested with for more than a few minutes. The new board should have everything needed to run CHAdeMO. I've heard that CCS is quite a bit harder.
@@realsolarcars wow a lot of hassles then but it's awesome that you're still revising, so impressed! I'm as keen as ever to get direct solar charging happening. And potentially while driving too, amazing! The amount of time you can drive is pretty small compared to charging time though so I'm happy to forego that if it adds extra time/cost. True, CCS is a nightmare and I wrote it off initially but I've since found SoCs that can handle all the comms stuff... the software part is then very doable for me (do it in my job). Hey if there's any way I can help out with your project I'd love to do so. I've been corresponding with Sam from Innovative a lot too. I'm building my own bifacial solar modules from cells - have 13 kW of them sitting in my apartment right now :)
@@realsolarcars Still excited to get my hands on the finished product. I was a little worried you had given up out of frustration James. Glad to hear you're still making progress on it.
@@realsolarcars whenever you have the boards ready, I’m interested in one. If you have the programming set up for your volt already, that would be ideal for me instead of an unprogrammed one. I’d be putting it in a 2012 volt to charge the main battery from 3 175w panels mounted horizontally, 2 on the roof one on the hood. Right now they’re charging a bank of 12v lead acid batteries which I can then charge over j1772 120v from an inverter which is obviously not ideal.
@@realsolarcars actually, since I have the battery bank already, would powering it from 12v batteries instead of directly from the panels be possible or is that too low of voltage? I could probably shuffle batteries around and get a different charge controller to bump up to 36v if needed.
Seems like if instead of vertical mounting if you mounted them closer to 45° in a v shape you would still take advantage of the bifacial power generation but increase the power to the front
Could you mention the specs on your DC/DC converter; current handling, voltage input Range, output voltage Range. Any cutoff voltage or cutoff current, i.e. simple Charger functionality? I know this is not yet a commercial kit or product, but you have threathened to make it one, and the alternative, which of, there are non outside a special order with CSIRO, or other arerospace electronics Companys, I really Hope you'll make this available, at least as PCB files and BOM as a purchasable download. Cheers!
Any boards offered for sale will have significant changes compared to the board shown on my channel, but the specs will be similar if not better. Input: 30-40v 10a MPPT Suitable for a 72 cell array. Output: 300-400v 1a Constant voltage if the battery is not able to accept all the power collected. I could add charge termination but I haven't done that yet since I'm not sure how to set it. The grid charger terminates at a higher current than the solar charger can generate. I intend to make the board fully programmable. That way people can adapt it to their own vehicles. That would save 90% of the effort involved. It's not just a charger. It's also a Programmable Logic Controller for operating the contactors.
@@realsolarcars Very nice, especially, the contactor control, I thought you'd run some fused cheat wires directly from your pack! The specs are bang in the Range I'm looking for. I have a programmable BMS that has settable triggers and outputs, so whatever final design you settle for, It Will be workable. Looking forward to this!
Great test of an interesting configuration. I've been planning to optimize my home solar PV for winter sun to reduce the huge delta between summer and winter. Did the vertical orientation cause any issues when driving?
@@paulkennett The goal was to avoid moving parts on the array mount. If it's going to move, it should be tilted optimally. Thankfully come wintertime I'll no longer need to park like a douchebag. 😇 I've actually put it back to horizontal because I want the extra kWh.
@@realsolarcars good going. Screw that guy for being bothered by YOUR hair. Biologically our hair isn't there for fashion. It's the external part of our nervous system. I myself have dreads since 1997.
Awesome... this is great data. I've been considering this on a boat hull
This is helpful as heck.
Thank you.
@11:50 Watching the power output go from 170 to 238 watts. It still surprises me how much power a little bit of shade can cost you. I noticed the same thing when I initially had my roof mounted panels under the roof rack. I could see this mounting method being very popular in Alaska or northern Russia though. It is very fascinating to consider how solar cars will adopt different necessary adaptations at different latitudes. Also I laughed me ass off at 16.19
Yeah, EV drivers are already accused of being smug, we shouldn't be doing stuff like that to make things worse. :-)
very interesting channel . Subscribed
The shadows of the struts / stays could be affecting your solar collection too, even a little bit of shading can limit the current from the whole string (of cells) AIUI.
So this is with your custom DC-DC converter again, it's been a few months since the last person asked so I will do it, how is that coming along? I gave up on his route because I want to be able to charge the battery to full, and get the OBC / BMS to do its balancing normally, also I'm too scared to mess up the BMS / required charging profile / destroy the wiring. My car only top balances and if it never gets there... that wouldn't be good. But mainly because I don't know how to make a DC-DC converter myself! 😛
I spent a long time looking into using the DC "fast" charge port, but the protocol is a nightmarish superposition of powerline comms, TCP/IP, home automation, XML (including auth!), TLS with private certs and after all that they end up with a one-way client-server protocol, atrocious. The losses with AC can be kept under control and with the EVSE you can even charge a friend's car if needed.
Your channel is very interesting, I’ve owned a 2012 Chevy volt for many years now and I love the car but with our Canadian winters the range drops to less than half. I end up burning just as much gas as a gas powered economy vehicle in the winter. I’m would be interested in perhaps adding an extra battery pack to charge when I’m parked using direct dc-dc charger or just simply tying the extra battery in in parallel, have you seen this or something similar done on a volt? I have access to almost limitless cheap lithium ion 18650 cells that could be used to make a pack with even more capacity the the original volts battery but don’t want to add too much weight. I’m considering eliminating the back seat for the extra battery rack since I never use it.
I finally got to test a Volt in cold weather. Ouch! The battery greyed out and the engine ran. Guess this was due to a cold battery. It was different than "Engine Running due to Temperature" which is caused by air temperature. The Volt expends a substantial amount of energy heating the battery. Maybe it would help to better insulate the battery and add an external battery heating pad. It could work like the Electrodacus system, splitting solar (or battery) energy between battery heating and battery charging.
My DC-DC could charge from a battery instead of solar. But with an output of about 500w it may not be enough to make a big difference. If a DC-DC could supply 2kw when the car was on, that would counteract the power used by the battery heater. www.enginer.us/ has a 5kw DC-DC. A big problem with an add-on DC-DC is that it won't heat a very cold battery before charging. My DC-DC would check battery temperature first, but it doesn't control the OEM heater.
If the power was ran through the J1772 port all of the factory battery heating logic would still operate. I have confirmed that the Volt will charge from 120v DC. But when I tested it I couldn't get over 6 amps. That may have been due to the battery internal resistance.
@@realsolarcars Yes, I did give some thought about adding a coolant heater in the battery coolant circuit to preheat my battery a perhaps run it on a battery when driving in cold weather to keep the battery warm. I recently removed my battery to replace the OEM heater for a unrelated issue but I decided to relocate it behind the engine for easy access for further experiments. I will post a video on my channel when I finally get the added heater installed. Cheers
How's the DC-DC converter going? Is the new board working well? I'm coming around to the idea that this is the only way to go now. The losses I'm seeing in my testing with solar array->MPPT->buffer battery->inverter->OBC->traction battery are just too high, and the OBC is the worst culprit. For those with CCS (like me) I now think it wouldn't be too hard to add a DC EVSE, could use one of the SoCs (found a couple for under $20) that implement the GreenPHY powerline comms.
The new boards were running too hot. A revised version was a lot better but still ran hotter than the original 2019 version. We felt it best to redo again to try and drop the temperatures some more. If all goes well they'll be available by June. It seems like we had a generous amount of beginner's luck on the first board. Being new to power design it's hard to know just how hot parts can run reliably. There were also issues like EMI and ringing that we just ignored on the first board. Considering how most tests went we thought for sure that there would be some issue with the car throwing a fit about our DC charger. Now we will use the charger while driving as well so it would be good to not loose radio reception to interference. The panel frames literally touch the antenna. Charging while driving add its own issue with ripple on the battery that we haven't tested with for more than a few minutes.
The new board should have everything needed to run CHAdeMO. I've heard that CCS is quite a bit harder.
@@realsolarcars wow a lot of hassles then but it's awesome that you're still revising, so impressed! I'm as keen as ever to get direct solar charging happening. And potentially while driving too, amazing! The amount of time you can drive is pretty small compared to charging time though so I'm happy to forego that if it adds extra time/cost. True, CCS is a nightmare and I wrote it off initially but I've since found SoCs that can handle all the comms stuff... the software part is then very doable for me (do it in my job). Hey if there's any way I can help out with your project I'd love to do so. I've been corresponding with Sam from Innovative a lot too. I'm building my own bifacial solar modules from cells - have 13 kW of them sitting in my apartment right now :)
@@realsolarcars Still excited to get my hands on the finished product. I was a little worried you had given up out of frustration James. Glad to hear you're still making progress on it.
@@realsolarcars whenever you have the boards ready, I’m interested in one. If you have the programming set up for your volt already, that would be ideal for me instead of an unprogrammed one. I’d be putting it in a 2012 volt to charge the main battery from 3 175w panels mounted horizontally, 2 on the roof one on the hood. Right now they’re charging a bank of 12v lead acid batteries which I can then charge over j1772 120v from an inverter which is obviously not ideal.
@@realsolarcars actually, since I have the battery bank already, would powering it from 12v batteries instead of directly from the panels be possible or is that too low of voltage? I could probably shuffle batteries around and get a different charge controller to bump up to 36v if needed.
Hello James!
Are you the same James that helps Foresty Forest with a quiet diesel heater?
Seems like if instead of vertical mounting if you mounted them closer to 45° in a v shape you would still take advantage of the bifacial power generation but increase the power to the front
Could you mention the specs on your DC/DC converter; current handling, voltage input Range, output voltage Range. Any cutoff voltage or cutoff current, i.e. simple Charger functionality? I know this is not yet a commercial kit or product, but you have threathened to make it one, and the alternative, which of, there are non outside a special order with CSIRO, or other arerospace electronics Companys, I really Hope you'll make this available, at least as PCB files and BOM as a purchasable download. Cheers!
Any boards offered for sale will have significant changes compared to the board shown on my channel, but the specs will be similar if not better. Input: 30-40v 10a MPPT Suitable for a 72 cell array. Output: 300-400v 1a Constant voltage if the battery is not able to accept all the power collected. I could add charge termination but I haven't done that yet since I'm not sure how to set it. The grid charger terminates at a higher current than the solar charger can generate.
I intend to make the board fully programmable. That way people can adapt it to their own vehicles. That would save 90% of the effort involved. It's not just a charger. It's also a Programmable Logic Controller for operating the contactors.
@@realsolarcars Very nice, especially, the contactor control, I thought you'd run some fused cheat wires directly from your pack! The specs are bang in the Range I'm looking for. I have a programmable BMS that has settable triggers and outputs, so whatever final design you settle for, It Will be workable. Looking forward to this!
Very cool project. I noticed you're not logging any solar kwh on your website's stats page. Why'd you stop charging?! :)
Great test of an interesting configuration. I've been planning to optimize my home solar PV for winter sun to reduce the huge delta between summer and winter. Did the vertical orientation cause any issues when driving?
Something about the vertical arrangement created a whistling sound. I didn't try to figure out why. I would guess it was the allthread.
@@realsolarcars I guess you could store them flat and raise them vertically when you "park like a douchbag" :)
@@paulkennett The goal was to avoid moving parts on the array mount. If it's going to move, it should be tilted optimally. Thankfully come wintertime I'll no longer need to park like a douchebag. 😇 I've actually put it back to horizontal because I want the extra kWh.
next time try doing of in the end. In front of each other
Thanks for not suggesting parking like a douchebag 😂
I'd like to write about your charging system. Sent you an email.
Please cut your hair
No.
@@realsolarcars why
@@Abe8816 You go first. Why should I cut my hair?
@@realsolarcars good going. Screw that guy for being bothered by YOUR hair. Biologically our hair isn't there for fashion. It's the external part of our nervous system. I myself have dreads since 1997.
Keep your hair long 👍