In the wikipedia article about [electromagnetic radiation][1] one can finde the following picture:
![enter image description here][2]


But shouldn't the E und B field be 90$^\circ$ out of phase? In the depicted way the energy isn't conserved. At 0 the energy is 0 and at $\frac{\pi}{2}$ the energy is maximal in both fields.


  [1]: http://en.wikipedia.org/wiki/Electromagnetic_radiation
  [2]: https://i.sstatic.net/2ADLi.png