commands in scripts are not working

[pacman401]

I want to save some watts during usage of my laptop so i read that i must use these commands:

echo 5 > /proc/sys/vm/laptop_mode
echo 1 > /sys/module/snd_hda_intel/parameters/power_save
echo 3000 > /proc/sys/vm/dirty_writeback_centisecs
cpufreq-set -c 0 -g powersave
cpufreq-set -c 1 -g powersave
ethtool -s eth0 wol d

I had put these commands in to /etc/rc.local (no effect), /etc/sysctl.conf (no effect)

every time I log in I have to "sudo su" in terminal and insert upper commands

btw I have compilled newest stable kernerl with CONFIG_SND_HDA_POWER_SAVE_DEFAULT set to 1 but that desn't help too