By Atul Gopal
The PluginIndia team got an opportunity to visit a unique startup in the EV space - Cellestial E-Mobility based out of Bengaluru. We actually interviewed the founder Mr Syed last year. So this was a visit to finally meet the team and see the tractor in action.
Video Interviews : Visit to Cellestial E-Mobility : Electric Tractor startup
Cellestial (note the double l, as in cell) is a 3 way partnership. Syed ji is providing his expertise with batteries. He is also the one who is coordinating for motors. The other partner is Siddharth, who is from Hyderabad. Sid runs a mech design back office, with a team of about 40 people. 12 of the team members have been deployed to Cellestial. And we have Ravi & Bhasker who run LoadStar, a Bangalore based company that is into the manufacture of airport tarmac tractors - and port container stackers. The smallish tarmac tractor weighs 10 t. It uses an Ashok Leyland engine - which powers a hydraulic pack. The wheels are driven by hydraulics because the delivery of torque is much smoother. The side plates of the tractor are 20 mm thick Mild Steel. The weight is important because you need to haul weights of as much as 110 t with the tractor.
The container stackers are really straight out of Discovery channel’s mega machines. Their height is about 20 ft. There is a joystick for operating the load. Even the steering is electronics based. The new machines complete the video game experience by providing an air conditioned cabin. The crane is powered by a 11 liter Volvo engine, which is imported from France. The max lifting load is around 20 t. It can stack containers upto 4 high. The height of lifting is calculated as per load. There are separate machines which are used for stacking empty containers. This baby weighs about 40 t - and sets you back by 4 crores. This is the bread and butter business for Loadstar. They make about 30-40 of these machines every year at the Peenya factory.
Did a test ride on the new tractor that the company has started work on. It is a small machine - what in trade jargon is called an orchard tractor. This is a hybrid design, as in quite a few parts that are used are from a conventional ICE tractor. Basically, like we see with Nexon and others from the electric car retrofit design, the engine gets replaced by a motor - and the story from there on remains the same for both ICE and Electric. So we have a clutch that connects to a huge flywheel. The flywheel is downsized to give a continuum between shift of gears, else unlike a ICE engine, when you take your leg off the pedal, the motor goes zero torque when you are re-engaging gears. The flywheel provides the momentum that continues to spin the motor shaft while the driver changes gears. The big plus of this whole arrangement is that the user will be totally familiar with all the controls - the numerous levers that are used to change gears and manipulate the Power Take Out (PTO) unit.
The container stackers are really straight out of Discovery channel’s mega machines. Their height is about 20 ft. There is a joystick for operating the load. Even the steering is electronics based. The new machines complete the video game experience by providing an air conditioned cabin. The crane is powered by a 11 liter Volvo engine, which is imported from France. The max lifting load is around 20 t. It can stack containers upto 4 high. The height of lifting is calculated as per load. There are separate machines which are used for stacking empty containers. This baby weighs about 40 t - and sets you back by 4 crores. This is the bread and butter business for Loadstar. They make about 30-40 of these machines every year at the Peenya factory.
Did a test ride on the new tractor that the company has started work on. It is a small machine - what in trade jargon is called an orchard tractor. This is a hybrid design, as in quite a few parts that are used are from a conventional ICE tractor. Basically, like we see with Nexon and others from the electric car retrofit design, the engine gets replaced by a motor - and the story from there on remains the same for both ICE and Electric. So we have a clutch that connects to a huge flywheel. The flywheel is downsized to give a continuum between shift of gears, else unlike a ICE engine, when you take your leg off the pedal, the motor goes zero torque when you are re-engaging gears. The flywheel provides the momentum that continues to spin the motor shaft while the driver changes gears. The big plus of this whole arrangement is that the user will be totally familiar with all the controls - the numerous levers that are used to change gears and manipulate the Power Take Out (PTO) unit.
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The motor is a 4 kW brush DC motor. Next version will be BLDC, or hopefully brushless. The current battery pack is 48 V NMC chemistry with about 8 kWh of storage. The pack weighs 60 kg. My biggest concern is battery capacity. I can understand the need for maintaining capital cost parity with an equivalent diesel tractor. But I am worried that it will lead to a disappointment in operations. The Cellestial team thinks that the battery has enough juice to do 1.5 to 3 hours of hard labour. And in haulage mode it can operate for 4.5 to 6 hours at 18 to 25 kmph speeds Field trials start in a week’s time, so we should start getting data soon on that.
Top speed is rated at 25 kmph. ARAI homologation work is going on - but electric tractor standards are still WIP at ARAI. The only other product that they have for comparison is the Sonalika tractor. My friend Mukesh informed me that Escorts has also got Austria based AVL to design and manufacture two electric prototypes for them. So like in the car space, most ICE tractor manufacturers are in wait-and-watch mode.
Did a small run of the vehicle inside the factory premises. The torque delivery is superb, thanks to the DC motor. Going back to my engineering college days, I remember that locomotives would use DC series motors back then - for the amazing starting torque that they had. I don’t think the tractor will face issues in tilling hard soils - or trudging up 20 degree inclines. Am not too sure about how much of regen can happen in an agricultural operation though. There is a fair amount of noise and vibration that happen in the tractor even at zero load. Of course, I am basing this comparison on my experience with cars and not other tractors. Am sure that the NVH is much lower than ICE tractors, but it definitely is some time away from car level smoothness. One of the reasons is the tyre tread, which will create vibration when ridden on concrete or asphalt. But the bigger reason for the racket is the presence of the essentially mechanical gearing that continues to power the wheels - and the PTO. The mechanism offers a choice of 9 gears in forward and 3 in reverse. Some of this gearing can definitely transition to electronic - and simplify the mechanical complications in future versions of this tractor.
I wonder about the role of machine weight in tilling and other agri operations. If we can come up with lighter designs which can serve the same purposes, then we can definitely have a positive impact on both capital and operational costs. Some inputs from our agricultural universities would be welcome in this space.
Dealers have been appointed in Jharkhand, Karnataka and Chhattisgarh. Most of these dealers are scions of agricultural families, who have spent times in cities working in typical IT jobs - who want to get some tech back to the agri eco system. Celestial has come up with an interesting design of a dealer workshop. It will be spread over 1.5 acres - with solar panels on the roof. The electricity generated will be used for charging the swappable battery packs. Sounds like an interesting idea. But the swap model still needs a little bit more of fine tuning. For small tractors, vehicle swapping is better than battery swapping. Less headache. As it is, tractors on rent are a norm in most villages. So maybe dealers can hire locals and train them specifically to operate these electric tractors and seed the market - as the agricultural sector rides the electric learning curve.
There are still a lot of loose ends that need to be tied up. I did not see any no-earth detection in the charger. Given the notoriously sad state of our rural electrical infra, am sure that the on board controllers can get into trouble if sufficient protection is not built into the machines themselves. The charger design should also take care of voltage and frequency fluctuations. The IP ratings are going to be be tested pretty rigorously in the slush of paddy fields. It would be interesting to see if the IP 65 rated battery packs withstand the water abuse. Or will they need to upgrade to IP67. One thing which definitely need to be part of testing is what happens when the tractor goes to a village washing center and is hosed down under high pressure. Will the connectors short? Will the insulation stand? Are the motor bearings sufficiently isolated to prevent sand and mud infiltration?
A lot of questions in our minds. And very soon the answers will start coming in from the fields. I do hope that the initial lot of tractors is fitted with telematics which give us these answers in real time.
At Pluginindia, we are really looking forward to Celestial revolutionizing the farm sector. And as the name indicates attaining great heights in this space!!
Top speed is rated at 25 kmph. ARAI homologation work is going on - but electric tractor standards are still WIP at ARAI. The only other product that they have for comparison is the Sonalika tractor. My friend Mukesh informed me that Escorts has also got Austria based AVL to design and manufacture two electric prototypes for them. So like in the car space, most ICE tractor manufacturers are in wait-and-watch mode.
Did a small run of the vehicle inside the factory premises. The torque delivery is superb, thanks to the DC motor. Going back to my engineering college days, I remember that locomotives would use DC series motors back then - for the amazing starting torque that they had. I don’t think the tractor will face issues in tilling hard soils - or trudging up 20 degree inclines. Am not too sure about how much of regen can happen in an agricultural operation though. There is a fair amount of noise and vibration that happen in the tractor even at zero load. Of course, I am basing this comparison on my experience with cars and not other tractors. Am sure that the NVH is much lower than ICE tractors, but it definitely is some time away from car level smoothness. One of the reasons is the tyre tread, which will create vibration when ridden on concrete or asphalt. But the bigger reason for the racket is the presence of the essentially mechanical gearing that continues to power the wheels - and the PTO. The mechanism offers a choice of 9 gears in forward and 3 in reverse. Some of this gearing can definitely transition to electronic - and simplify the mechanical complications in future versions of this tractor.
I wonder about the role of machine weight in tilling and other agri operations. If we can come up with lighter designs which can serve the same purposes, then we can definitely have a positive impact on both capital and operational costs. Some inputs from our agricultural universities would be welcome in this space.
Dealers have been appointed in Jharkhand, Karnataka and Chhattisgarh. Most of these dealers are scions of agricultural families, who have spent times in cities working in typical IT jobs - who want to get some tech back to the agri eco system. Celestial has come up with an interesting design of a dealer workshop. It will be spread over 1.5 acres - with solar panels on the roof. The electricity generated will be used for charging the swappable battery packs. Sounds like an interesting idea. But the swap model still needs a little bit more of fine tuning. For small tractors, vehicle swapping is better than battery swapping. Less headache. As it is, tractors on rent are a norm in most villages. So maybe dealers can hire locals and train them specifically to operate these electric tractors and seed the market - as the agricultural sector rides the electric learning curve.
There are still a lot of loose ends that need to be tied up. I did not see any no-earth detection in the charger. Given the notoriously sad state of our rural electrical infra, am sure that the on board controllers can get into trouble if sufficient protection is not built into the machines themselves. The charger design should also take care of voltage and frequency fluctuations. The IP ratings are going to be be tested pretty rigorously in the slush of paddy fields. It would be interesting to see if the IP 65 rated battery packs withstand the water abuse. Or will they need to upgrade to IP67. One thing which definitely need to be part of testing is what happens when the tractor goes to a village washing center and is hosed down under high pressure. Will the connectors short? Will the insulation stand? Are the motor bearings sufficiently isolated to prevent sand and mud infiltration?
A lot of questions in our minds. And very soon the answers will start coming in from the fields. I do hope that the initial lot of tractors is fitted with telematics which give us these answers in real time.
At Pluginindia, we are really looking forward to Celestial revolutionizing the farm sector. And as the name indicates attaining great heights in this space!!
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