Bicycles, Motors, Batteries and Chargers

A place to discuss all things involving power and lighting. Generator tips, alternative energy, lighting your camp/bike/art/self and more.

Bicycles, Motors, Batteries and Chargers

Postby unjonharley » Mon Apr 25, 2011 1:48 pm

/

Starting this thread to learn more about electric motor assist bicycles..

Pice of gas is so much I'm cutting back on hualing shit to Burning Man..
Might even drop the trailer all togeather..

Figure I can sell all my bikes and buy a nice cruiser and add a hub motor assist for about $400 $500..

Problem one is charge time.. 4-6 hours..

Will a cheap 45 watt Harbor Frieght solor panel do the trick??
That would leave the extra cost of two sets of batteries.. OK..
Do I solor to convert to inverter for charging?? Or can the bateries be seporated and charged 12volt off the panels// Will be running 24volt..

Can I use heavyer deep cell battery, carried in a bike trailer.. Or will the higher amps damage the motor??? Already have the bike trailer to haul a sound system..

Come on guys, Let us dumbys pick your brains..+++
User avatar
unjonharley
 
Posts: 8789
Joined: Tue Sep 09, 2003 11:05 am
Location: Salem Or.

Postby capjbadger » Mon Apr 25, 2011 2:45 pm

No exactly an answer to your question, but this site has tons of good info. Plus they have a sweet deal going on for their plans. It's something like only 10 cents more for 6 plans than it would be to buy 3 plans.
http://www.atomiczombie.com/

I got 3 plans from them (didn't see the special like a dummy). They are pretty nice. They do require welding.

-Badger
Arrrggg!! Avast ye fucking fluffy bunny shirtcockers! Haul your drunken hairy fat ass out of our sight or prepare to receive a hot buttered hedgehog fired up your aft quarters!

Honey Badger don't care. Honey Badger don't give a shit!
User avatar
capjbadger
 
Posts: 2692
Joined: Sun Jun 19, 2005 1:17 am
Location: Horus' Left Armpit
Burning Since: 2005
Camp Name: Lamplighters

Postby unjonharley » Mon Apr 25, 2011 3:00 pm

capjbadger wrote:No exactly an answer to your question, but this site has tons of good info. Plus they have a sweet deal going on for their plans. It's something like only 10 cents more for 6 plans than it would be to buy 3 plans.
http://www.atomiczombie.com/

I got 3 plans from them (didn't see the special like a dummy). They are pretty nice. They do require welding.

-Badger


Already have the bike and trailer figured.. Hub motor can come all made up to you wheel spec's. In my case I'm going for the front wheel power.. The whole kit comes to around $400.. With battery, controler and thumb throtel.

Now trying to get around the 6 hour of generator noise..
User avatar
unjonharley
 
Posts: 8789
Joined: Tue Sep 09, 2003 11:05 am
Location: Salem Or.

Postby Elorrum » Mon Apr 25, 2011 3:03 pm

I spent a lot of time in the V is for Voltage forums on pedelecs when I was researching my electric bike conversion.
http://visforvoltage.org/forums/electri ... d-pedelecs
What's the name of the act? The Aristocrats.
User avatar
Elorrum
 
Posts: 4473
Joined: Sat Mar 15, 2008 9:09 pm
Location: San Jose, CA

Postby gyre » Mon Apr 25, 2011 3:26 pm

I personally wouldn't go solar at this point.
Cheaper to chip in on someone's generator expenses and it's minimal draw for any large generator anyhow.
Rather than spend money on solar, buy better batteries.
NIMH or nicad can recharge fast.
Lithium types also to a lesser degree.

Matched battery packs cost more and seem to be worth it, with panasonic, for instance, etc.

You can use any size battery you like, as long as the voltages are correct.
Basic kits don't really have a proper controller which makes a difference.
The cheaper euro hub I have is like this.
Adding a good controller is more efficient.
I find the lack of direct control very annoying at slow speeds too.

Be sure to look at the motor gearing if you don't get one that drives through the gears.
For towing or large loads, you probably need a low gear.

Quality chargers matter a lot too.
Heinzmann is considered best in hub kits and has many choices.
Panasonic is considered the best driven gear kit.
I have a giant pana, chinese with all japanese electrics.

You're in the middle of electric bike central out there, even near the giant importer.
Look at used bikes first.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby FIGJAM » Mon Apr 25, 2011 3:38 pm

With all the reading I did before going electric, Im not sure where I gleened this info from, so maybe someone can clerify.

It seems that a cars alternator charges at 40amps (on average) and regular battery chargers at 6 or 12amps.

So would just running jumper cables from the car and running it for an hour be equel to 4 to 6 hours on a regular charger?
"Don't buy ur Burn...........Build ur Burn!"

Fuck Im Good Just Ask Me
User avatar
FIGJAM
 
Posts: 7072
Joined: Thu Mar 25, 2010 10:39 am
Location: apache junction az.

Re: Bicycles, Motors, Batteries and Chargers

Postby capjbadger » Mon Apr 25, 2011 3:38 pm

unjonharley wrote:Will a cheap 45 watt Harbor Frieght solor panel do the trick??
That would leave the extra cost of two sets of batteries.. OK..
Do I solar to convert to inverter for charging?? Or can the bateries be seporated and charged 12volt off the panels// Will be running 24volt..

Can I use heavier deep cell battery, carried in a bike trailer.. Or will the higher amps damage the motor??? Already have the bike trailer to haul a sound system..

Come on guys, Let us dumbys pick your brains..+++

To put it in gas vehicle terms, Amps is the size of your gas tank. Nothing wrong with having a bigger gas tank. :)
Voltage you DO need to match up with your motor controller and motor. Too much voltage will fry things.

I don't know how much the bike/motor would use, so it's hard to say on the solar panels. They will charge the batteries. The question is how long will it take.
Watt = Volts x Amps
So if that's a 12volt, 45 Watt solar array, then it's only putting out 3.75 amps/hour. If your battery is say 12v 100AH and it's half empty after riding around all night, at very best you're looking at 50AH/3.75AH=13.33 hours to fill the "tank" back up.
That's the simplified math. It would actually be longer than that.
That's a simple, but extreme example. Again, the charging time all depends on how many amps the motor is using (an thus how much you have to replace to refill the battery).

For solar charging, you don't need an inverter. You need a solar charging regulator. It will pass the DC current to the batteries and monitor when they are charged. You can charge them off the bike (12v) or on the bike (24v). All depends on your regulator.

You must use deep cycle batteries. Regular car (starting) batteries will be killed by this kind of use. They're not built for it. Some batteries clam to be deep cycle but really are not. If they have "cold cranking amps" listed in their specs, they are not real deep cycle.
Golf cart batteries are a good example of real deep cycle. They mostly come in 6v, but you can find them in 12v as well. They are also HEAVY. Deep cycle batteries have much thicker lead plates in them than car batteries.

That should get you started. Oh, also look up and understand hooking Batteries/Solar Panel up in Series as vs Parallel.
Series adds volts, Parallel adds Amps.

-Badger
Arrrggg!! Avast ye fucking fluffy bunny shirtcockers! Haul your drunken hairy fat ass out of our sight or prepare to receive a hot buttered hedgehog fired up your aft quarters!

Honey Badger don't care. Honey Badger don't give a shit!
User avatar
capjbadger
 
Posts: 2692
Joined: Sun Jun 19, 2005 1:17 am
Location: Horus' Left Armpit
Burning Since: 2005
Camp Name: Lamplighters

Postby gyre » Mon Apr 25, 2011 3:50 pm

There are deep cycle versions of car batteries that can be used for cranking, but the golf cart versions use heavier (and simpler) plates,

There is a diminishing return with weight on a bike though.
If you spend enough on a deep cycle lead battery, you've wasted money better spend on nimh or nicad etc.

I have used larger cranking batteries to good effect by never depleting them in charge and use cycles.

Mr Fixit used a larger lead battery on his bike but I'm not sure the type.
Maybe a motorcycle battery?
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby capjbadger » Mon Apr 25, 2011 3:52 pm

gyre wrote:NIMH or nicad can recharge fast.
Lithium types also to a lesser degree.

Say what? :shock:
The charge times are the same for equal AH, but LiPOs don't self discharge, are vastly lighter, no "memory" effect, can provide more power at once (C1, C2, C3).
LiPO packs knock that socks off older tech like NIMH and Nicads. The newer LiFePO4 (lithium iron phosphate) are even better. :)

Of course they are fucking expensive. :(

-Badger
Arrrggg!! Avast ye fucking fluffy bunny shirtcockers! Haul your drunken hairy fat ass out of our sight or prepare to receive a hot buttered hedgehog fired up your aft quarters!

Honey Badger don't care. Honey Badger don't give a shit!
User avatar
capjbadger
 
Posts: 2692
Joined: Sun Jun 19, 2005 1:17 am
Location: Horus' Left Armpit
Burning Since: 2005
Camp Name: Lamplighters

Postby capjbadger » Mon Apr 25, 2011 3:54 pm

gyre wrote:There is a diminishing return with weight on a bike though.
If you spend enough on a deep cycle lead battery, you've wasted money better spend on nimh or nicad etc.

I have used larger cranking batteries to good effect by never depleting them in charge and use cycles.


Agreed. You really don't want to use old school lead acid batteries on a bike if you can avoid it. I would avoid Nicads though. NiMH's or Lithium...

-Badger
Arrrggg!! Avast ye fucking fluffy bunny shirtcockers! Haul your drunken hairy fat ass out of our sight or prepare to receive a hot buttered hedgehog fired up your aft quarters!

Honey Badger don't care. Honey Badger don't give a shit!
User avatar
capjbadger
 
Posts: 2692
Joined: Sun Jun 19, 2005 1:17 am
Location: Horus' Left Armpit
Burning Since: 2005
Camp Name: Lamplighters

Postby gyre » Mon Apr 25, 2011 3:57 pm

FIGJAM wrote:With all the reading I did before going electric, Im not sure where I gleened this info from, so maybe someone can clerify.

It seems that a cars alternator charges at 40amps (on average) and regular battery chargers at 6 or 12amps.

So would just running jumper cables from the car and running it for an hour be equel to 4 to 6 hours on a regular charger?

You can charge at different rates.
There is usually a penalty in battery life for fast charging.
Better chargers can minimize damage or even eliminate it.

Alternators should charge on demand, but a full 40 amps over the load demand from the rest of the vehicle shoud be rare, and actively avoided really.
The average alternator won't produce that much power except at high rpm anyway.
Look for ratings at different rpms.
All should have at least two ratings.
Better ones have an idle rating too.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby gyre » Mon Apr 25, 2011 4:06 pm

capjbadger wrote:
gyre wrote:There is a diminishing return with weight on a bike though.
If you spend enough on a deep cycle lead battery, you've wasted money better spend on nimh or nicad etc.

I have used larger cranking batteries to good effect by never depleting them in charge and use cycles.


Agreed. You really don't want to use old school lead acid batteries on a bike if you can avoid it. I would avoid Nicads though. NiMH's or Lithium...

-Badger

I would have thought so, but there are some advantages in fast charge and discharge applications and cost can be very low now.
They seem to match up for series packs better too.

Some companies are sticking with them for these reasons.

The pana matched packs are about $400-450 and I think heinzmann is similar.
Larger lithium packs have heat issues, and the cost skyrockets, though some claim vast cycle numbers for these.

Charge caution for larger nicad/nimh is advised also though.
The scooter kit I have once had a stunningly beautiful pack of this type and blew up dramatically during a charge cycle.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby capjbadger » Mon Apr 25, 2011 4:09 pm

Yeah, batteries are one of those "You get what you pay for" things. You pay one way or another. :|

-Badger
Arrrggg!! Avast ye fucking fluffy bunny shirtcockers! Haul your drunken hairy fat ass out of our sight or prepare to receive a hot buttered hedgehog fired up your aft quarters!

Honey Badger don't care. Honey Badger don't give a shit!
User avatar
capjbadger
 
Posts: 2692
Joined: Sun Jun 19, 2005 1:17 am
Location: Horus' Left Armpit
Burning Since: 2005
Camp Name: Lamplighters

Postby gyre » Mon Apr 25, 2011 4:09 pm

Note that there are multiple lithium types now.
At least two distinct types currently.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby gyre » Mon Apr 25, 2011 4:22 pm

capjbadger wrote:
gyre wrote:NIMH or nicad can recharge fast.
Lithium types also to a lesser degree.

Say what? :shock:
The charge times are the same for equal AH, but LiPOs don't self discharge, are vastly lighter, no "memory" effect, can provide more power at once (C1, C2, C3).
LiPO packs knock that socks off older tech like NIMH and Nicads. The newer LiFePO4 (lithium iron phosphate) are even better. :)

Of course they are fucking expensive. :(

-Badger

As power increases, lithiums become more limited, and require monitoring just to prevent self immolation.
Raw lithiums are available, but many are unaware of the required management needed.
I think the tesla has 28000 regulators and an overall restrictor when heat is detected.
Prius use a similar protection scheme restricting charging even more.
Toyota still had issues with heat and explosion, with their very conservative approach.

The nickel style just tolerate more heat and abuse.
There are limits even with them.

When slow charging, a well designed lithium pack should match, I would think.
My pana charger goes through multiple cycles to take advantage of the nimh attributes while maximizing life.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby FIGJAM » Mon Apr 25, 2011 4:34 pm

I'm useing true deep cycle 105ah agm batteries.

The forums are saying the stock alternator is putting out 55amps at 600rpm. (idle)

I dont think it takes that much fuel to run the truck for an hour and does'nt it stop charging when the batt is topped of?

Or am I just full of shit? :?
"Don't buy ur Burn...........Build ur Burn!"

Fuck Im Good Just Ask Me
User avatar
FIGJAM
 
Posts: 7072
Joined: Thu Mar 25, 2010 10:39 am
Location: apache junction az.

Postby gyre » Mon Apr 25, 2011 5:08 pm

What kind of truck and what size (nominal) alternator?
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby unjonharley » Mon Apr 25, 2011 5:10 pm

/

I use a personal transporter for shopping trips.. Also load it into the van and take it close to other shops.. Give me more electric range..

The transporter uses 2x6 12volt gel batteries for 36volt.. Charge time 6 hours off 110volt..
These same type 12ah batery are offered with bike kit I'm looking at.. There claim is 20 mile to a charge.. unknown more when assisted peddeling..

As for charge time. I was thinking of two sets of batteries.. One working the other charging.. I play mostly in the day time a BM..

A few years back I made a set up for charging.. (had no idea what I was doing) Anyway, Gas motor spining an alternater to a starting battery then ainverter to a charger.. The starter battery could keep up ok with the charger..
User avatar
unjonharley
 
Posts: 8789
Joined: Tue Sep 09, 2003 11:05 am
Location: Salem Or.

Postby gyre » Mon Apr 25, 2011 5:30 pm

Gel batteries are common, but have some heat and charge and discharge limitations.

I would take the mileage estimates by dealers with a huge grain of salt.
Look at the packs most consider adequate for 30 mile range.
Much larger than the stock size, typically 6-10 amps.

Consider the extra weight you'll carry and the playa surface.
I strongly suggest you vet the load carefully before using a standard hub vs lower geared one.

There are some cheaper ones considered useful on the forums, though often with some modification.
They do make chinese lower geared sets, but I don't know how available they are.
Counterfeits are an issue.
Noise is an issue often mentioned with the cheaper ones.

Lead cells, even gels are probably more tolerant of abuse than other types.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby gyre » Mon Apr 25, 2011 5:37 pm

Toyota says lithiums pattern, as do others.
That's why they use the charging/discharge cycle they do, mostly 40-60% if I remember correctly.

The cycles available from lithium and li phosphate are heavily disputed already.
The big issue may be usage, as charger sophistication solved so many ni/nimh issues.

Lithium is damn sure lighter though, and that has big returns on bikes.

On the scooter, I think the pack was putting out 40 to 50 amps under full throttle, something a lithium pack couldn't do, but it would have been a lighter setup with lithium.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby some seeing eye » Mon Apr 25, 2011 5:39 pm

Hub/ system maker http://www.ecospeed.com/ and many completed electric bike shops are in Portland, Oregon: Splendid Cycles, Clever Cycles, Greenlight Bikes. Good for ideas or copying designs, or even complete bikes or cargo bikes and trikes. Probably similar businesses in larger cities.

In the past, the mobility camp has charged batteries through your 110VAC charge controller for free. There was also a large solar array, over 300sf, near the AEZ in '09 charging for free. The AEZ boards may know more current info.
User avatar
some seeing eye
 
Posts: 994
Joined: Tue Sep 09, 2008 12:06 pm
Location: The Oregon
Burning Since: 1999
Camp Name: Woo

Postby gyre » Mon Apr 25, 2011 5:47 pm

I saw the solar array put out a real 20 kw during mid day.
Very impressive.
No junk.


Portland and Seattle may have the highest concentration of electrics in the usa.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby unjonharley » Mon Apr 25, 2011 5:47 pm

/
There is no extra weight.. One set of batteries will be in camp charging..

Distance on the transporter is rated at 21 miles.. At power drop off to about half at the 11 mile mark.. It becomes slower and slower.. Never ran it below 1/3 charge..

Going with the hub motor will make the bike more useable year around..

I have trouble with water and the conector on the transporter.. The wireing and controls will be more protected on a bike.. Will have to work on water proofing the hub motor.. So I can use it year around.
User avatar
unjonharley
 
Posts: 8789
Joined: Tue Sep 09, 2003 11:05 am
Location: Salem Or.

Postby gyre » Mon Apr 25, 2011 5:58 pm

I meant extra weight over the typical lightweight bike, cargo etc.

Definitely get the best set you can for year round use.
Water will be a consideration in your area.
The forums know more than I do.

The giant is a known quantity in water use, if it would work for you.
Ultra efficient 250 watt motor on the pana version.

The heinzmann also.
I have a Leco hubmotor.

I may be able to help with connectors.
Some look similar but never fail with water.

Have you looked at the longtail conversion and the stokemonkey?
Love it, but rare still.
I haven't found any used at all.
You might be able to engineer your own motor with their adapter parts.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Postby FIGJAM » Mon Apr 25, 2011 6:47 pm

gyre wrote:What kind of truck and what size (nominal) alternator?


98 chevy 3/4 ton 4x4 6.5 turbo diesel.

130amp alternator.
"Don't buy ur Burn...........Build ur Burn!"

Fuck Im Good Just Ask Me
User avatar
FIGJAM
 
Posts: 7072
Joined: Thu Mar 25, 2010 10:39 am
Location: apache junction az.

Postby gyre » Mon Apr 25, 2011 8:02 pm

http://www.k0bg.com/alternator.html
Some tech info on alternators and heavy duty use.

There were two 130 a units on those years.
They made some up to 250 A.
I found some doing 120A at idle 500 rpm.

The article raises some duty cycle issues on units not made for continuous use like ambulance units.

It could be doing 55A with the regulators made now.
I think gas use may surprize you though.
I can't confirm the output, though it shouldn't be hard to check.
Sounds high but possible.

As for charging regulation, designs vary.
A separate charger can be more efficient and protect the battery better though.

I was told not to ever put a fully discharged battery load on my alternator if I had a choice, but charge it off board first.
They said they are only designed for maintaining a charge.

The heavy duty units would be different, and have heavier wiring too.
I know of idle output up to 160A and I think 220A has been mentioned.

The stock gm units don't seem to have a good reputation for voltage stability or reliability, even without non stop use.

WOW!
Here's a serious approach.
http://www.aurasystems.com/pages/prod_intro.html
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ


Re: Bicycles, Motors, Batteries and Chargers

Postby aflash » Fri Mar 09, 2012 3:00 am

There's another good motorized bike and electric bike forum at http://www.motoredbikes.com/ with heaps of information
aflash
 
Posts: 1
Joined: Fri Mar 09, 2012 2:55 am

Re: Bicycles, Motors, Batteries and Chargers

Postby gyre » Fri Mar 09, 2012 8:58 am

aflash wrote:There's another good motorized bike and electric bike forum at http://www.motoredbikes.com/ with heaps of information

I may have mentioned them at one point.
Note that it is a locked forum currently.
User avatar
gyre
 
Posts: 15346
Joined: Sun Aug 07, 2005 6:01 pm
Location: ΦάÏ

Re:

Postby Canoe » Fri Mar 09, 2012 5:07 pm

gyre wrote:Toyota says lithiums pattern, as do others.
That's why they use the charging/discharge cycle they do, mostly 40-60% if I remember correctly.

You'll toast your lithium cell if you under-voltage it. Different cells have different voltage specs.

Having a lithium pack of cells isn't safe enough. Each pack should have a Battery Management System (BMS) built into the pack. They usually include a temperature sensor. Should protect for over-voltage, under-voltage, max charge current, max discharge current. Better ones will protect from an outright short-circuit.

The BMS also affects charging. Some packs charge and then have to sit and rebalance the charge. Others have voltage detection of each cell and adjust the charge voltage per cell in a series so they charge equally - no waiting for a rebalance after charging.
Note that although you may be safe on the total max/min voltage for a series of cells, due to manufacturing variance, an individual cell may over or under voltage and fail the pack. Some pack builders will test cells and (like high-end audio components) will match cells of like performance. This avoids the cost of a per-cell BMS and they use/monitor a total pack voltage for under/over voltage, be it internal or external to the physical pack. This has more risk as a cell within a pack may change over time to out of spec with the other cells in the pack. Common for a failed lithium pack to be due to a single cell; replace it, and you're good to go. The per-cell voltage monitoring is safest, doesn't require matched cells to be safe (although for optimum efficiency, matched cells is technically the best). Currently, a per-cell BMS for up to 13 cells in series can be had for around $20. The LiFePO pack I built has a per-cell BMS that protects to the limits I chose, but I also monitor the pack's total voltage with an external voltage monitor that will alarm on whatever voltage I select (I pick up slightly above under-voltage so I know when the charge is getting low).

Different lithium battery chemistries have different properties, voltage limits, flammability of the internal fluid if it leaks, etc.. Research what works for your needs.

Note that if you're building your own pack (or buying one ready made from who knows who), that lithium cells need to be physically restrained to prevent their physical expansion and rupture. Some cells can be purchased as the pure cell without a containment package, as you're supposed to link them and then contain the pack. Others come individually packaged, like the blue headway cells, which also includes a leak-containing expansion area (reminiscent of smokeless/flashless shotgun shells); should the internal cell have an expansion failure, the leak is contained within the external shell. (photo lower right shows the expansion end: the sealed expansion cap is behind the visible metal end - note the holes for the air to escape from between the visible end and the sealed expansion cap)
Headway 38120.jpg

Headway had 10Ah cells, then 12Ah and now 15Ah. Which means some deals can be had for 10Ah and 20Ah packs made with the older 10Ah cells.

If you have a project that will require a lot of cells (some people power cars with the headway cells), I hope you can wait a while. Looks like we may have a game changer just around the corner.
45ah-cells.png
You do not have the required permissions to view the files attached to this post.
*** http://www.burningman.com/preparation/ ***
... but don't harm the red dragon that frequents the area from time to time. He and I have an agreement.
.
“Dear subscriber, you are registered as a participant in a mass disturbance.”
User avatar
Canoe
 
Posts: 1778
Joined: Sun Jul 31, 2011 8:01 pm

Next

Return to Power & Illumination

Who is online

Users browsing this forum: No registered users and 0 guests