Using a MEP generator to charge your EV?

[Chainbreaker]

Well according to this article it can be efficient to use a diesel generator to charge an Electric Vehicle.

What I found quite interesting is that in this particular test it suggests that it was more efficient to burn the diesel in a generator charging an EV than to burn diesel in a typical diesel-powered vehicle.

Note that the generator/charging station in this article provided 50 kW DC output. Wonder if the charging station itself has a AC to DC converter to accomplish that?

PS: Let's please not drift off to making any political comments in this thread so we don't get derailed & banished to the "Mess Hall" a paying member only thread participation. This is about the possibility of using a MEP generator to charge an Electric Vehicle and/or home battery bank AC production and the efficiencies of doing so.

 

[nextalcupfan]

I've thought about using my 803a to charge a battery bank for my house rather than running the generator 24/7.
Diesels seem to be most efficient when working in a specific load range.
You just have to get the charging output to around the most efficient load on your generator.

 

[98G]

I've thought about using my 803a to charge a battery bank for my house rather than running the generator 24/7.
Diesels seem to be most efficient when working in a specific load range.
You just have to get the charging output to around the most efficient load on your generator.

I'm thinking this would net you the most recovered energy from the diesel fuel used. This would allow you to run the genset at >80% load while charging.

There's system losses from the charging process, but these losses should be measurably less than the losses from running the genset at less than peak efficiency.

The larger the genset, the greater the advantage of using a battery bank as a buffer.

For charging an EV, some of the same applies. The improved efficiency of a (non emissions compliant) diesel genset compared to an (emissions compliant) on-road diesel engine isn't trivial. Further, the diesel genset engines generally convert diesel fuel to energy more efficiently than a diesel engine that has to make enough instantly-on-demand power to accelerate a vehicle.

Using a 5000-6000lb brick shaped vehicle and a MEP802 as points of calculation, and a 75% efficiency rate of battery charging, back-of-the-envelope says ~40miles @50mph for a gallon of diesel. Could be off by a factor of 2 in either direction, depending on how accurate my assumptions were.

 

[nextalcupfan]

If we could charge an EV for an hour and see how many miles it gains on it's range that would be ideal I think.
Just need to make sure the charger is around 80-100% load on the generator.

I just did a quick search and a Tesla model S under perfect conditions can do 4 miles on 1kWh charge.
An 803a can put out 12.5kWh at 100% while burning around a gallon of fuel so that would equal about 50 miles per gallon of fuel burned.

 

[rickf]

Are you talking about regular 220 charging or the High energy chargers that are 460 volt? Big difference in charge times and the length of time the diesel has to be running, hence the amount of fuel used.

 

[Mullaney]

.
I have wondered if a pickup truck design - with space in the bed of the truck - would be a way to carry your charger with you... You know, BYOC (Bring Your Own Charger). I know nothing and have no real desire to own one - but could an EV move while being charged?

 

[98G]

.
I have wondered if a pickup truck design - with space in the bed of the truck - would be a way to carry your charger with you... You know, BYOC (Bring Your Own Charger). I know nothing and have no real desire to own one - but could an EV move while being charged?

While I have no idea if current EVs are capable of being charged while in motion, there's no reason you can't make one that could be.

Consider though, at that point you've made a vehicle that goes down the road powered by an onboard running engine and you've put a bunch of additional crap between the engine and the wheels.... or alternatively consider diesel electric trains and subs....

 

[Chainbreaker]

I've thought about using my 803a to charge a battery bank for my house rather than running the generator 24/7.
Diesels seem to be most efficient when working in a specific load range.
You just have to get the charging output to around the most efficient load on your generator.

Yes, using one's MEP to store electrical energy via a battery bank is more efficient than I realized. Also, this captures the otherwise lost energy produced by those periodic exercising/maintenance runs we do with our gensets to keep them working. A win-win if you're also storing that energy to be used for electricity in an EV or stored in batteries for house AC consumption.

 

[Chainbreaker]

While I have no idea if current EVs are capable of being charged while in motion, there's no reason you can't make one that could be.

Consider though, at that point you've made a vehicle that goes down the road powered by an onboard running engine and you've put a bunch of additional crap between the engine and the wheels.... or alternatively consider diesel electric trains and subs....

Plus you've now got the added weight of the generator that an EV has to expend energy to carry. Though, similar to the Australian test situation circumstances I linked, if you were taking an EV offroad, or where EV charging stations are few & far between possibly out of range for EV, it could make the difference of making it to your final destination by having onboard charging capability.

 

[Chainbreaker]

Are you talking about regular 220 charging or the High energy chargers that are 460 volt? Big difference in charge times and the length of time the diesel has to be running, hence the amount of fuel used.

Not sure who that question was directed at... But my intent was exploring using the MEP generators members already have to charge an EV, or for that matter recharging a bank of batteries for house/shop electrical consumption purposes. So that would pretty much rule out 460 volt unless one has access to one already.

 

[Chainbreaker]

Another efficiency of sorts, is monetary efficiency, if you have access to off-road diesel your burning "cheaper diesel" in your generator than an on-road diesel vehicle consumes.

 

[kayak1]

While I have no idea if current EVs are capable of being charged while in motion, there's no reason you can't make one that could be.

Consider though, at that point you've made a vehicle that goes down the road powered by an onboard running engine and you've put a bunch of additional crap between the engine and the wheels.... or alternatively consider diesel electric trains and subs....

EVs normally won't let you drive while they are plugged in. They will make you remove the plug before being able to put the car into drive. (You might be able to fix this with via making a software change).

Some EVs have a range extender that will charge the battery as the car drives such as the BMW i3:

What Is The BMW i3 Range Extender? | Autobytel

The BMW i3 an electric vehicle with a 22 kWh (18.8 kWh usable) battery that gives it a range of 80-100 miles. ECO PRO mode can increase the range by 12% by adapting the accelerator pedal response whil

www.autobytel.com

 

[kayak1]

Not sure who that question was directed at... But my intent was exploring using the MEP generators members already have to charge an EV, or for that matter recharging a bank of batteries for house/shop electrical consumption purposes. So that would pretty much rule out 460 volt unless one has access to one already.

I haven't seen a USA EV that can support > 277v AC when charging. AC charging is based on the onboard charger that is build into the car. Older Tesla's could charge up to 19.2kW (80 amps, 240 volts), current Tesla's can charge at up to 11.52kW (48 amps, 240 volts).

Car's like the Nissan Leaf have smaller onboard chargers 6.6kW or the older ones only could go up to 3.3kW.

DC charging a current Tesla is currently limited to 600 amps at current pack voltage (~400 volts). This normally maxes out around 250kW. Other cars have other limits.

 

[rickf]

Chainbreaker, This is what I was talking about, the level three chargers. I am not a gen-set expert but I am pretty sure that 50 Kw DC set would manage that wouldn't it? And I am positive some of the bigger AC sets would run those chargers. In that link I put down there the section on Level 3 chargers say most municipalities will probably not allow you to put one in your home because of the danger. Sounds like a challenge to me.


"What is a Level 3 charging station?


Level 3 charging stations (also known as Direct Current Fast-Chargers) use a 480 Volt system and can add up to 250 km of range per hour charged. In many cases, you can charge an EV's battery to 80% in 30 minutes. This will vary depending on the battery size and its level of charge."

What Are the 3 Levels of EV Charging Stations?

A trained professional should perform a preventative inspection and repair work on your electrical control panel if any of these conditions exist:

www.maderelectricinc.com

 

[Chainbreaker]

Chainbreaker, This is what I was talking about, the level three chargers. I am not a gen-set expert but I am pretty sure that 50 Kw DC set would manage that wouldn't it? And I am positive some of the bigger AC sets would run those chargers. In that link I put down there the section on Level 3 chargers say most municipalities will probably not allow you to put one in your home because of the danger. Sounds like a challenge to me.

"What is a Level 3 charging station?

Level 3 charging stations (also known as Direct Current Fast-Chargers) use a 480 Volt system and can add up to 250 km of range per hour charged. In many cases, you can charge an EV's battery to 80% in 30 minutes. This will vary depending on the battery size and its level of charge."

What Are the 3 Levels of EV Charging Stations?

A trained professional should perform a preventative inspection and repair work on your electrical control panel if any of these conditions exist:

www.maderelectricinc.com

Very informative article, thanks! So, judging by the charging times shown in the spreadsheet contained within the highlighted hypertext in my initial post the "Tritium" branded charger they used fed by the large generator sitting next to it had to be a Level 3 charger.

However, what I am am interested in discussing is mainly the use of a MEP with 120/240 capability to supply Level 2 charging rates. However, if one has only a Level 1 or Level 3 capable generator that's not out of the realm discussion here. There are Pros & Cons I'm sure.

Of course, if one has a 5kW model MEP generator vs a 10kW or greater, the amps difference would obviously impact charging times. Personally, I would be content with taking a few hours to charge an EV at home or a house battery bank augmented with solar panels. I've always been of the mindset that slow charging is gentler on batteries than hi-rate fast charging due to heat buildup. However, it seems that newer Li-ion EV batteries may be more tolerant of fast charging.

 

[nextalcupfan]

Personally I like the idea of Graphene batteries.
According to what I've read they seem to act similar to normal lithium batteries but handle high speed charging way better.

 

[kayak1]

Very informative article, thanks! So, judging by the charging times shown in the spreadsheet contained within the highlighted hypertext in my initial post the "Tritium" branded charger they used fed by the large generator sitting next to it had to be a Level 3 charger.

However, what I am am interested in discussing is mainly the use of a MEP with 120/240 capability to supply Level 2 charging rates. However, if one has only a Level 1 or Level 3 capable generator that's not out of the realm discussion here. There are Pros & Cons I'm sure.

Of course, if one has a 5kW model MEP generator vs a 10kW or greater, the amps difference would obviously impact charging times. Personally, I would be content with taking a few hours to charge an EV at home or a house battery bank augmented with solar panels. I've always been of the mindset that slow charging is gentler on batteries than hi-rate fast charging due to heat buildup. However, it seems that newer Li-ion EV batteries may be more tolerant of fast charging.

I have played with charging when the power is out, I have never had to charge in anger when the power was out.

A number of times when the power has been out I have just plugged into a 120 plug to top the car off so as not to waste the solar that I can no longer sell back to the grid.

When the power is out I change where my EVSE (level 2 charger) is plugged into, set the EVSE to charge at 5kW (20amp), and at that point, I can charge via the batteries/solar. With the MEP-802 connected, I will still be able to charge at night if I need to.

I plan on using a car to load test the 802, I have a 2nd L14-30 outlet on order to connect to the MEP-802a. I have unbonded the generator thus it will still be connected to the house for the ground/neutral connection (I have a temp connection via a 10/3 with ground). When wood prices drop I will build a shed and put a pad mount for the 802 next to it. The car only cares about the two hot and ground legs.

 

[Chainbreaker]

Excerpt taken form post # 3

....I'm thinking this would net you the most recovered energy from the diesel fuel used. This would allow you to run the genset at >80% load while charging...

Also, during these longer genset runs what if you could also capture some of the gensets exhaust heat to pre-heat the water going into your house water heater? I have visions of an extended exhaust exiting into & passing through the outer surfaces of coiled copper tubing with the internal water fed to a nearby water heater. Not sure how much heat gain gets transferred into the water but hey if we are eeeking out efficiency of burnt diesel might be a possibility to harvest some of that excess heat being given off.

 

[kayak1]

Excerpt taken form post # 3



Also, during these longer genset runs what if you could also capture some of the gensets exhaust heat to pre-heat the water going into your house water heater? I have visions of an extended exhaust exiting into & passing through the outer surfaces of coiled copper tubing with the internal water fed to a nearby water heater. Not sure how much heat gain gets transferred into the water but hey if we are eeeking out efficiency of burnt diesel might be a possibility to harvest some of that excess heat being given off.

I once had a coworker that had a cogen box in his basement instead of a boiler.

Cogeneration Systems｜Energy Systems｜YANMAR

The introduction of Micro Cogeneration from Yanmar.

www.yanmar.com

I think that it's much better to keep it outdoors, like an outdoor wood boiler.

 

[Chainbreaker]

Now that is marketing/advertising at its best! Right after posts discussing level 2 chargers a "MaxiCharger Level 2 Chargers" ad appears below.

Pretty cool

Edit: Hmmm, now no ad's showing? I seriously thought it was a good thing that if we are being served ad's that having relevant content ads was a good thing. I actually selected the ad that came up because it was of interest... versus something like a clothing ad.