How to reduce consumption on arduino system? -

this simple example.
how reduce total power consumption without modify hardware,
, modify program???
of course delay(1000) shouldn't changed.

thank everyone.

ps. because after see video

http://v.youku.com/v_show/id_xmtmxndc0ndaxng==.html?f=26075379&from=y1.7-3&utm_campaign=newsletter-cn-sep2015-taiwan%28v1%29&utm_medium=email&utm_source=eloqua,

and want applicate on project. still don't know how use ""picopower""to reduce arduino system.

// pin 13 has led connected on arduino boards.   // give name: int led = 13;  void setup() {                     pinmode(led, output);      }  void loop() {       digitalwrite(led, high);        delay(1000);                    digitalwrite(led, low);         delay(1000);                }