There are many engineering challenges to making ocean energy more efficient. Ocean energy can produce 10-20% of the energy needs of smaller countries that border major oceans. The Netherlands is one good example. Presently,most wave-energy technologies are in their formative years. Critics argue that the amount of energy produced by even 10000 wave machines is to small.It can barely provide enough power for a large city.The further inland the electricity has to go,the more power it uses. To send electricity from a wave-generator to the shore would be highly inefficient. it would have to go from the Atlantic Ocean to the shore,then over 1000 km to cities like Chicago.