devkit-power: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/devkit-power - from package: DeviceKit-power

You may install the required package with command yum install {package}

Error in other languages:
devkit-power: bevel nie gevind nie
devkit-power: comandă negăsită
devkit-power: comando não encontrado
devkit-power: commande introuvable
devkit-power: command not found
devkit-power: käsku ei ole
devkit-power: không tìm thấy lệnh
devkit-power: komanda nerasta
devkit-power: Kommando nicht gefunden.
devkit-power: kommandot finns inte
devkit-power: komut yok
devkit-power: nie znaleziono polecenia
devkit-power: níor aimsíodh an t-ordú
devkit-power: no se encontró la orden
devkit-power: no s'ha trobat l'ordre
devkit-power: opdracht niet gevonden
devkit-power: parancs nem található
devkit-power: perintah tidak ditemukan
devkit-power: príkaz nenájdený
devkit-power: příkaz nenalezen
devkit-power: команда не найдена
devkit-power: командата не е открита
devkit-power: 命令找不到
devkit-power: コマンドが見つかりません