Develop Bugs

Battery Consumption Questions

Hi guys,
I have to say, compared to my HTC Hero and Modaco 3.2 rom, the battery life on the Desire seems pretty poor to say the least.
Do you have any tips? I know there are mixed views on task killers but whats the general consensus? Seems like every app that gets opened, seems to stay open forever or atleast open in the background on this thing. Is that good or bad?
Does the Gmail app which is push based I believe consume less battery than say the HTC Mail app used to sync about every half an hour?
Have you discovered any particular HTC apps that drain more battery than normal?
I've already disabled Facebook and Friendstream completely, use seperate apps for those.
It just feels like the battery eats away even when the phone is just sat there with the screen off, sure I have 3G on but Twicca is the only thing set to update every half an hour in the background and the Gmail app on push no doubt.
Any tips?

pretty sure if u slightly decrease the brightness of the screen and stop all data connections unless you want to run them will help the battery life

disable live wallpapers
disable auto updates
disable 3G (just for the sake of trying)
decrease the brightness or make it auto (dont put it to the max)
put plain black wallpaper as background (trust me it consumes 40% less than the colored wallpaper, again, do it just for the sake of trying)
try this for one day and see if you get anything different

I have the brightness set really low, don't use live wallpapers.
I would disable 3G but that kind of defeats the purpose of having twitter updates and stuff, one of the main features of the phone.
Just checked and Twicca is only set to update once an hour, this is really weird.

Arthur Hucksake said:
I have the brightness set really low, don't use live wallpapers.
I would disable 3G but that kind of defeats the purpose of having twitter updates and stuff, one of the main features of the phone.
Just checked and Twicca is only set to update once an hour, this is really weird.
Click to expand...
Click to collapse
I saw somewhere that you can see what app is draining your battery life in the notification bar, just open the notifications bar and go to battery, and see if you find anything related there

I have the phone for 3 days and I'm still in the stage where I play with it all the time.
Day 1: fully charged at 1PM, used the phone pretty much non-stop till 10PM and finally plugged it in with 3% left;
Day 2: unplugged the phone at 8AM, had it in stand-by for couple hours, then used it non-stop for 2 hours, then 4 more hours of stand-by, then it 2 hours continous use. The rest was more or less stand-by. Plugged it in at 10PM with around 10% left.
Day3: used it quite a bit on and off during the day, still have 34% left.
I don't do any fancy power saving, though I don't like apps updating themselves, except for mail. However, I use WiFi when I can and I listen to podcasts whenever I walk/drive somewhere.
It's a bit too early to draw conclusions, but at this point I'd say that Desire's battery life is much better than G1's (I had 1600 mAh battery).
Of course it all depends on particular use case. Also, maybe the network is spotty in your area - that might drain a lot of battery.

A positive battery story....

I let my phone discharge fully till it turned itself off!
Charged it for 4 or 5 hours.
Now I used it to make 3 short calls (5mins each) and send 10 or so texts, and surf for about 5 minutes, use google sjy mpas for 5minutes, showcase some video to some friends 2mins, general messing 10mins altogether.
Phone is up 40hours now (since charge) and still at 80%. I am very impressed.
I put it to airplane mode between 12am and 7am though as I don't like to be woken by drunk friends texts at 2am etc. (it happens sometimes).
I think those of us (me included) who slated the battery life originally didn't relaise we were using the phone non-stop pretty much for the entire day, trying out all the features on it. I doubt the first week of use will be "typical use" for ANY user
Happy Days

My battery on day one seems fine, 12.5 hours running so far, screen at 100%, everything on automatic syncing (and I mean everything, Weather, Twitter, FB, Gmail etc), continuous WiFi connection throughout, plenty of "first day" playing around and still sitting at something like 20%. With a few more charges and more typical use will last a day just fine, which is all I ask, since I always charge my phones overnight...

When i got my phone i let it run out as it had half power, i overcharged it a few hours then let it die, then i do the same again but not overcharge it and let it die. Now i charge it when i need to but i seem to be getting 3 days worth with usage out of it and i use gps, web and have things on auto. Seems to be much better than when i first had it as the battery didnt even last a day but now its past 2 days.
I assume with newer firmwares etc this will improve

My battery life seems to get worse. I charged it fully ... it has been on for 6 hours and I have put 3g on for a while (1hour max and i barely have used it) and my battery is already 60% ... is that poor?? This is my second phone as well!!!

mcgon1979 said:
I let my phone discharge fully till it turned itself off!
Charged it for 4 or 5 hours.
Now I used it to make 3 short calls (5mins each) and send 10 or so texts, and surf for about 5 minutes, use google sjy mpas for 5minutes, showcase some video to some friends 2mins, general messing 10mins altogether.
Phone is up 40hours now (since charge) and still at 80%. I am very impressed.
I put it to airplane mode between 12am and 7am though as I don't like to be woken by drunk friends texts at 2am etc. (it happens sometimes).
I think those of us (me included) who slated the battery life originally didn't relaise we were using the phone non-stop pretty much for the entire day, trying out all the features on it. I doubt the first week of use will be "typical use" for ANY user
Happy Days
Click to expand...
Click to collapse
I thought a full charge only required 3 hours..?

Anyone having surprisingly short battery life go into the phone keypad and dial in *#*#4636#*#*, when you key in that last * you will be taken to a testing menu (I've added a contact with this number and when in the dialer I can long press on the number as select edit number before calling to take me to this screen)
In this menu there are options to see phone and battery information as well as usage statistics for apps. The best battery option is "battery history" this shows you what apps are using your battery for various things such as network and processor usage. You can see this data for since you last rebooted your phone, unplugged it or for the whole life of the phone.
The first important part is "other usage", "running" shows you the percentage of the time your phone has been awake and doing stuff, "screen on" is the percentage of time your screen has been on, the difference between these two is when your phone has the screen is turned off but the phone is still working such as when syncing. Ideally you want these two percentages to be as close together as possible but it depends on how much syncing you have going on automatically in the background. If your running percentage is at or near 100% then an app is keeping your phone awake and using battery.
Next we have "partial awake use", this is what as been running in the background when you have the screen turned off and any apps that process or sync in the background would be listed here, the longer the bar, the bigger the drain on your battery. On my phone now the biggest bar by far is android system but it is still only small.
With "sensor usage" this is what has been using your sensors, games that use the sensors will feature heavily here.
"Gps usage" is again pretty self explanatory, whatever has been using gps.
"Network usage" was a real eye opener for me, I found out that an app was downloading megs of data all day and dwarfed all the other bars and was the reason for my bad battery life. Here the blue part of the bar is download and the red part is upload.
And lastly "cpu usage" on mine these are all practically non-existent but if anything is using massive amounts of processing it will show up here.
I only found out about this the other day but it has helped my battery life substantially, I used to take it off charge in the morning and be down to around 60% by lunch time, now I'm at 98%. I did this by uninstalling any apps that used too much battery and that I didn't really use very much as well as the vampire apps that were running and syncing continuously in the background, I also reduced the frequency at which some of my services such as stocks, email and weather synced, and used it on a low brightness when possible.
This is my first android device and I can now happily use it without the fear of running out of battery before the days end

Wow, thanks andybut85, that was a very informative post!

If you download Spare Parts from the Market it gives you access to the same info - instead of 'dialing' to test mode.

andybut85 said:
Next we have "partial awake use", this is what as been running in the background when you have the screen turned off and any apps that process or sync in the background would be listed here, the longer the bar, the bigger the drain on your battery. On my phone now the biggest bar by far is android system but it is still only small.
Click to expand...
Click to collapse
My biggest is "Calendar" (54mins from Boot, compared to 1min for Andriod System!)
What Calendar could this be? Im syncing from Google Calendar, so will it be that? If so, wouldnt my email syncing show up as constantly on too?
Or could it be some other App that is making it run constantly?
Any help gratefully received.

myk202020 said:
My biggest is "Calendar" (54mins from Boot, compared to 1min for Andriod System!)
What Calendar could this be? Im syncing from Google Calendar, so will it be that? If so, wouldnt my email syncing show up as constantly on too?
Or could it be some other App that is making it run constantly?
Any help gratefully received.
Click to expand...
Click to collapse
Have a look for "Total in all time" with mine the calendar is roughly half that of android system, it could be that recently your calendar has had to sync for a long time, this could be a one off or if it's still high for the total time it could be a deeper problem. You could also try rebooting and seeing if it occurs again.

Have a look for "Total in all time" with mine the calendar is roughly half that of android system, it could be that recently your calendar has had to sync for a long time, this could be a one off or if it's still high for the total time it could be a deeper problem. You could also try rebooting and seeing if it occurs again.
Click to expand...
Click to collapse
Calendar: 1day 7hrs
Android: 5hours
I'm thinking some app I've put on yesterday is not letting it sleep. will uninstall stuff one by one and see how it goes.
Sent from my HTC Desire using the XDA mobile application powered by Tapatalk
Click to expand...
Click to collapse

I'm still having problems with battery drain.
My Desire will not last a day
Installed Juiceplotter to find out when and why my battery drops so fast.
See attached image.
The battery drains very fast when i USE the phone, so when the screen is on. (20% in one hour)
I have two push email account activated, one with the HTC Exchange, and one with TouchDown.
But that doesn't explain the drops when phone is active.
Anyone else having this kind of batterydrain ?

I have positive "story" about battery too. Im on second charging. Saturday at 1:00 Im unplug it from charger and now 34h later Im on 7/10 battery.
Im make few calls(cca. 10 calls long 1-3min), few times(cca. 3-5x) check emails accounts(4 pop3 email accountes), quick test sygic navigation, little search on market(install calendar widget and some other app), and play few levels of Teeter...
3G is turned ON
GPS, WIFI is turned OFF
Also automatic sync is for most things disabled or setup to sync 1x per day...

Hmm Can't say I'm impressed by my battery life... it dropped 20% overnight..
I''ll keep an eye out on what's running and see if i can fine tune, but turning things off seems to be a bit pointless as it is made for use not just sit on a desk being pretty.
regards
Kef

i got great battery life at home over the weekend connected to my wi-fi network.. i have a feeling its the crappy edge reception in my office thats eating into battery life during the week..

micks_address said:
i got great battery life at home over the weekend connected to my wi-fi network.. i have a feeling its the crappy edge reception in my office thats eating into battery life during the week..
Click to expand...
Click to collapse
yep, that sounds highly plausible. Bad or weak connections to the network (especially mobile internet connections) will really drain a battery as the phone needs to use more power to maintain adequate connection strength.
you can check your signal strength in the "settings / network strength" section. I notice in good 3G areas my connection is -95dBm or higher. At work (which is in some sort of black spot in Dublin) I only get EDGE connection and my signal strength is about -80 to -85dBm. I bet this makes a big difference to battery life, especially if I try browsing or data connection.

my signal strength at work is -91 dbm...
i'm guessing bigger numbers are worse?
mcgon1979 said:
yep, that sounds highly plausible. Bad or weak connections to the network (especially mobile internet connections) will really drain a battery as the phone needs to use more power to maintain adequate connection strength.
you can check your signal strength in the "settings / network strength" section. I notice in good 3G areas my connection is -95dBm or higher. At work (which is in some sort of black spot in Dublin) I only get EDGE connection and my signal strength is about -80 to -85dBm. I bet this makes a big difference to battery life, especially if I try browsing or data connection.
Click to expand...
Click to collapse

spare parts showed me that "media" was using the network a lot, bowever i cant work out what this corresponds to, it says DRM protected content storage, download manager and media storage. shows as having downloaded several megs
i use spotify for music, anyone any ides what these could be?
thanks

only guess but i'd say its spotify.. i have used servcies like that in the past on my pc.. and they sometimes have a lot of downloading going on that you dont even ask for!... worth checking out..
kinkade said:
spare parts showed me that "media" was using the network a lot, bowever i cant work out what this corresponds to, it says DRM protected content storage, download manager and media storage. shows as having downloaded several megs
i use spotify for music, anyone any ides what these could be?
thanks
Click to expand...
Click to collapse

micks_address said:
only guess but i'd say its spotify.. i have used servcies like that in the past on my pc.. and they sometimes have a lot of downloading going on that you dont even ask for!... worth checking out..
Click to expand...
Click to collapse
yes it could be, but spotify also comes up as a separate user of resources and i tested it since unplugging when spotify wasnt running and "media" still comes up as the biggest user.
makes me think that its not spotify

Android System eating the battery

Hey all, I don't know if anyone has even noticed on their Evo's but on mine, the Android system usually eats most of the battery. I noticed there is a ton of processes under Android system that are running compared to like five on my Hero. I've never seen the core system processes take up more than maybe 15% of the battery, but right now, I'm at like 41% with 16m 6s of CPU total and 47s of CPU foreground. If anyone knows why this is or a way to fix it, please let me know. I'm on the first MR update. I've been able to get a lot of battery stuff figured out, if I can get the system to calm down, then I should be able to get even better battery life than my Hero.

I'm seeing the same thing, android system is at 96% battery use after letting the phone sit overnight. Never saw that on my nexus, this is strange.
Could be related to the fact that everything is syncing up, I just activated last night too.
-------------------------------------
Sent via the XDA Tapatalk App

Yeah, the system seems to have calmed down a bit today, though I also have the OC widget running to keep the processor lower during sleep. I'm guessing its helping, but I'm not sure if there is something else to get it down. I almost never even saw the System show up in usage on my Hero, now its one of the top contributers. I got used to having custom roms on the Hero, but so far all I need on the Evo is unrevoked. I know a lot of people around here don't like it, but I found I only needed a couple of apps that require root and so far love it. That OC widget really comes in handy.

maybe i can clear things up a little bit for you guys...what you see in the battery use section is distributed across 100% of the time since you last had it plugged in. if you notice all the percentage numbers add up to 100%.
if you plug your phone in and turn it on and off on you will see that android system is probably around the 90's thats because android system has used 90+ percent of the phone since you plugged it in....over time that number will lower, becuase other things will start using the battery power... what you see is a percentage based on time. not based on whats actually working RIGHT THEN AND THERE do you guys understand?

I too am having that problem and at 15% battery life warning - it still shows my Android system @ 40-44% usage after 8hrs of work.
I mostly text message all day long due to work - make phone calls and recieve calls from work every hour. GPS on for no more than 15min all day long to get direction when my keymap book doesnt help.
4g off, bluetooth off, background data 15 min only (gps) than off, gps off when not in use, mobile network (3g) off when not in use.
I would have figured my screen being on would have drained my battery life since I check text message every 10-15mins for 8hrs...
So went to work at 9am, 100% life
got off work 6pm, 25% life
I've done all the tricks, cdma only, force stopped a bunch of apps, goggle talk off, sync off, making sure maps/gps has been closed (forced or not)
still disappointed with battery life.
Unrooted Evo
My crappy AT&T Razr lasts me 2-3days with text message + call + 1.5hr of playing Bejeweled a day

*facepalm* you guys don't get it....

grrgrrgrr said:
I too am having that problem and at 15% battery life warning - it still shows my Android system @ 40-44% usage after 8hrs of work.
I mostly text message all day long due to work - make phone calls and recieve calls from work every hour. GPS on for no more than 15min all day long to get direction when my keymap book doesnt help.
4g off, bluetooth off, background data 15 min only (gps) than off, gps off when not in use, mobile network (3g) off when not in use.
I would have figured my screen being on would have drained my battery life since I check text message every 10-15mins for 8hrs...
So went to work at 9am, 100% life
got off work 6pm, 25% life
I've done all the tricks, cdma only, force stopped a bunch of apps, goggle talk off, sync off, making sure maps/gps has been closed (forced or not)
still disappointed with battery life.
Unrooted Evo
My crappy AT&T Razr lasts me 2-3days with text message + call + 1.5hr of playing Bejeweled a day
Click to expand...
Click to collapse
check your hardware version there is a thread about different types of evos and it seems like everyone who has the hardware revision 0001 has really bad battery life. i would exchange your device.

Yes we know, Freelancerx, or at least I do. But after over 8 hours and the system is still using more of the battery than anything else is a little disturbing. Never seen that on any other device. I have Hardware 0002.

I have this same issue with hardware version 0002. I run Fresh 1.0.1, i use Netarchy-toastmod kernal, have latest radio. I have also tried Damage Control (did get slightly better battery life out of DC but not amazingly different)
after 7 hrs since unplugged my andriod system is at 39%, cell standby 28% phone idle 20% display 9%.
i dont have bluetooth, wifi or 4g on. I use juicedefender+ultimate to turn off apn when screen is not on. I use set CPU to underclock when i am unplugged and go down to 128 when screen off and i am Stilll lucky if i make it all day with moderate usage.
Every day it is the same andrioid system is around 40% of the usage for the time it was unpluged.
the following is listed under included packages (not sure if this shows the same for everyone or if it shows what packages are running)
BRCMBluetoothService - Bluetooth is not on so if it shows packages running this may be an issue
Sync Feeds - I have all android syncs off and mail at 6 hours
settings storage
Rosie Utility
Acounts & syync
Account and sync settings
settings
HTC Widget Download Manager
Network Location
Setup
HTC Checkin service
Checkin serivce
VPN services
Android system
Wonder if there is something to the android system on these (ie something not turning off that should) or if we are all just crazy and happen to get the same results.

I had a hardware 0002 model and often experienced the same thing with high system % usage.
My phone was replaced, due to a screen issue, and now I have the 0003 model and seems system % is much lower so far.
I haven't installed any system update yet, so I am on the first original release rom (not rooted yet).
Going to be testing it for a few days before I update and root, so I can make a fair comparison between the original and current oem's.

If your phone is on....Android system is being used.

satch12 said:
If your phone is on....Android system is being used.
Click to expand...
Click to collapse
I think everyone here understands this. the question i think we are trying to figure out is why with similar usage and configurations some people get 40-60% android systems usage while others get 10% over the same period of time.

Android system is way too high.
satch12 said:
If your phone is on....Android system is being used.
Click to expand...
Click to collapse
Yes but if it is configured in an optimal way then android system is always beneath cell standby and phone idle.
For example, today after 15h 28m 23s since unplugged I have...
Cell stanby 38%
Phone idle 37%
Android System.....12%
That is with background processing with auto syncing every hour or so.

Conserving battery, Hungry apps etc

Hey guys, thought it might be a good idea to share with each other what apps/settings are mauling their battery life...
Personally at the advice of beards, I used systempanel app to try and monitor app cpu usage etc.
I was experiencing large battery drain overnight, so I decided to leave it running for 1 night. By the morning I had lost about 30 or 40% of battery and systempanel told me that Fancy Widget was using about 11 or 12% avg of cpu (if I remember correctly).
I removed Fancy Widget, turned off Data (with APNswitch) and also stopped systempanel (which prob contributed some of the usage itself) when I went to sleep the other night and the batt was at 40% usage. In the morning I turned on my phone and was greatly surprised to learn that the phone was STILL AT 40%... didn't even lose 1% wooooot
So.. I'd like to put my suggestions out
Batt hungry apps: FancyWidget (maybe...? but I'm surprised that other people don't seem to have a problem so maybe its my human error?)
Phone settings:
Data:3G data seems to consumes a lot!!!
I suggest leaving on 2G if you want to keep auto syncing apps etc, and swapping to 3G when you really need the speed (browsing/downloading).
If you want to totally maximise battery usage, turn off data completely every time you put the phone on standby, and turn off all autosyncing apps.
I also believe Wifi consumes less battery than 3G usage, although I haven't done any serious testing, I managed to use wifi on and off for about 5 hours at a lanning event and I still had a fair bit of batt left.
Recommended apps:
I recommend APNswitch to turn off data. I like it because you can use it as an app, not just a widget, as I've found all the APN widgets too be ugly. It also uses the notification bar wisely
Other experiences:
According to systempanel, samsung widgets (feed, buddies, daily briefing) all consume very little CPU (less than other widgets in my experience. I've kept them all as they seem beautiful to me
To XDA members, anyone else experience bad batt life with fancy widget?
Please feel free to critisize any of my claims, I hope we can help each other out with sharing battery life tips, good/bad apps etc.
EDIT:
Wallpapers:(thanks gadjet0)
Live wallpapers seem to consume a lot. Also having read discussion about the power consumption of oleds, I put a pure black background on my device. Whether it's actually reducing power or not I have no scientific evidence.

Thanks should pin this!
Sent from my GT-I9000 using XDA App

Have you tried any live wallpaper, I got the feeling that they put a drain on the battery!

Yes, all its true what have writed oswade. I was make this thing with my Galaxy, and battery life have very growing...
Regards

also try tasker, I have set profiles to put phone into airplane mode at night, during day the data is off, but comes on every 15 mins or when the screen is turned on (like juicedefender i think its called) works brilliantly and conserves battery.
I can unlpug phone at 5am and still have around 60% at 9pm with light usage, while before I would get to evening and battery would be close to dead!

Glad that I'm not the only ones.. I suffered quite bad. Full charge ard 6pm..was playing robo zone for an 1hr+. Batt left 50%. Arghh..
Does black or darker background uses more batt?
I'm using beautiful widget.
Sent from my GT-I9000

oswade said:
Hey guys, thought it might be a good idea to share with each other what apps/settings are mauling their battery life...
Personally at the advice of beards, I used systempanel app to try and monitor app cpu usage etc.
I was experiencing large battery drain overnight, so I decided to leave it running for 1 night. By the morning I had lost about 30 or 40% of battery and systempanel told me that Fancy Widget was using about 11 or 12% avg of cpu (if I remember correctly).
I removed Fancy Widget, turned off Data (with APNswitch) and also stopped systempanel (which prob contributed some of the usage itself) when I went to sleep the other night and the batt was at 40% usage. In the morning I turned on my phone and was greatly surprised to learn that the phone was STILL AT 40%... didn't even lose 1% wooooot
So.. I'd like to put my suggestions out
Batt hungry apps: FancyWidget (maybe...? but I'm surprised that other people don't seem to have a problem so maybe its my human error?)
Phone settings:
Data:3G data seems to consumes a lot!!!
I suggest leaving on 2G if you want to keep auto syncing apps etc, and swapping to 3G when you really need the speed (browsing/downloading).
If you want to totally maximise battery usage, turn off data completely every time you put the phone on standby, and turn off all autosyncing apps.
I also believe Wifi consumes less battery than 3G usage, although I haven't done any serious testing, I managed to use wifi on and off for about 5 hours at a lanning event and I still had a fair bit of batt left.
Recommended apps:
I recommend APNswitch to turn off data. I like it because you can use it as an app, not just a widget, as I've found all the APN widgets too be ugly. It also uses the notification bar wisely
Other experiences:
According to systempanel, samsung widgets (feed, buddies, daily briefing) all consume very little CPU (less than other widgets in my experience. I've kept them all as they seem beautiful to me
To XDA members, anyone else experience bad batt life with fancy widget?
Please feel free to critisize any of my claims, I hope we can help each other out with sharing battery life tips, good/bad apps etc.
EDIT:
Wallpapers:(thanks gadjet0)
Live wallpapers seem to consume a lot. Also having read discussion about the power consumption of oleds, I put a pure black background on my device. Whether it's actually reducing power or not I have no scientific evidence.
Click to expand...
Click to collapse
How did you stop "systempanel"?

borchgrevink said:
How did you stop "systempanel"?
Click to expand...
Click to collapse
Couldn't figure that out either... probably need to use a task-killer or reboot.

So what do you recommand (or anybody else) to replace Fancy Widget ?
I don't really want a HTC like Clock but I want a digital clock like this ?
Beautiful Widget for exemple ?
And i don't know why an app which automatically turn on/off the 3G when ur using the brownser/market doesn't exist already ? That will be great !!!

What's wrong with fancywidget? Seems fine on my device.

If using Juicedefender,do I still need Advanced Task Killer?

Then What?
Hi!
We have industry best hardware configuration.
But we
1) can not Use live wallpapers
2) can not Use 3G for many hours
3) can not Use considerable number of applications from the market
4) can not watch two full length movies
5) etc.................
If you want above
1) Purchase additional battery and put in your pocket
2) Power adapter/ Travel adapter always carry with u
If you are roaming for more than six hours, then it's bad.
this is not only for Galaxy S most of the samart phones fall in this.
What can we do????????
-G

Dude, I have a Samsung Galaxy Ace
As soon as I got it I installed fancy widget and some other programs. My phone was lasting only 6 hours. I sync to corporate, gmail, facebook and a few others. At first I thought 'bad phone'. I uninstalled Fancy Widget last night and voila my phone is fine. It'll last a day+ now.
What the hell is wrong with that app?? Why does it need so much compute? Its just a widget that shows time??

what would be the best kernal for me to have ?

my battery drains like a bugatti veyron doing 252mph constantly
so what would you advise . is the kernal i have now the best or should i change .. i dont want to reall lose much performance on what i have now but would like the battery to maybe improve if possible ...
from full charge taking plug out searching market for 2 mins the battery drains 5-8% in matter of mins
and i have only had the phone a week

With that kind of drains the problems the kernel won't change that much. There is probably a app that causes the battery drain so looking in to that will have more effect. Also the brightness/screen on is the biggest drain and kernel won't do much about that.
You said that you have the phone a week, the battery needs some time to reach it's full potential and you probably use the phone a lot because it's new. So use the phone normally for another week, after that week let the phone drain until it shuts itself off, leaf it off and charge it till it's full. (there is a different calibration method but this always worked for me)

What do you have now? Stock or rooted?
Sent from my HTC Desire using XDA App

First of all, I would assume that you don't use the phone non-stop (it would be justified to lose power in a few hours if you're on it non-stop).
I recently had issues with power consumption as well. What I did was:
1) check the built in battery monitor: menu-settings-about phone-battery-battery use. The bad thing about this monitor is that it does not differentiate well the apps consuming power, but you can still see if there's something wrong, as the most consumption should come normally from the screen and voice calls. For me, the most consumption was made by com.htc.bg, which, if I let the monitor on for a few seconds, would transform in the calendar app. Weird stuff. I unchecked the calednar auto sync from menu-settings-accounts and sync. It may have slowed the power loss down, but not significantly. I noticed a significant loss of battery by WiFi. I realized, I needed more information so:
2) I installed an app called 'Power Tutor'. What it does is, it calculates which apps consumes power, and it shows you in percentages. After install, you need to start the 'power profiler'. It will appear in your notification bar. If you let it run, after a few hours, you can see in "view application power usage" who is using power. That's how I discovered that my winamp app was really off the charts using power like crazy. So I went in the winamp settings, and I unchecked some options that could have determined this power consumption, like wireless sync, automatic mount as USB drive, etc. There was actually an option that was overriding the wifi power management, stating that the wifi does not stop after 180 seconds of standby. Basically, if you have wifi on, and you stop using the phone for 3 minutes, the phone automatically turns off the wifi. This was not happening any more, due to winamp. So I unchecked all those options, and voila. It worked, I have now normal battery life.
Good luck!

be aware of a couple of things
1. battery drain for the 1st few weeks are high because of a couple of factors, the battery "learns" and gets conditioned over a period of time (doesnt use the old 16hr charge process). its a new device for you so its a novelty, you probably mess about with it with the screen on more than you think.
2. there is a configuration within HTC's builds and in the memory chip of the battery to stop over charging. the device will charge to 100 and then slowly deplete to 90% while still saying full on the phone. as soon as you disconnect it recalibrates to the correct value which is anywhere between 90% and 100% depending at which part of the cycle you catch it

Some other tips to increase battery life, from a friend of mine in the Romanian forum:
1) use the app watchdog, it will warn you when an app is using too much of the processor and will ask you if you want to close it.
2) juice defender with the paid add-on 'ultimate juice' - with the correct settings... it's amazing.
3) Dial *#*#4636#*#* - phone information-network type: select gsm auto prl. The phone will stay on 3G when it has good signal, and switch to 2G when it doesnt, saving battery
4) Change the wallpaper to a static one, not a live one.
5) Go to menu-settings-accounts and sync and increase sync intervals for weather, news, or even set them to sync manually when you choose.

i will try and answer everything at once ..
ok my screen is on 13% brightness
i hardly ever use my phone , the only real use was to root , s-off, put ROM ETC ON
I reply to about 50 texts ish per day and search the market for literally 1-2 mins to see what new apps are in
i dont play games or anything
the thing the battery uses most is the screen and as i say i have it on monochrome theme with 13% brightness, there is nothing synced , i check automatically for email etc .. actually beautiful widgets is set to auto update every 4 hours
i never use wifi as i have a 3gb download/data usage, i dont use gps ...well i do but i have had no need to .. thats about all i can tell ya
rastaman the pt2 is a bit weird it should stay at 100 if just taken out of charge

I calibrated the battery and that made no difference.
Sent from my HTC Desire using XDA App