Ok so I created a block called PowerTest.

Please bare in mind im not the best modder out there im still learning im making this mod to learn more .

package com.zombiesurvival.blocks;

import com.zombiesurvival.power.pipes.BlockPipe;
import com.zombiesurvival.tileentity.PowerTestTileEntity;

import net.minecraft.block.Block;
import net.minecraft.block.BlockContainer;
import net.minecraft.block.material.Material;
import net.minecraft.block.state.IBlockState;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.server.gui.IUpdatePlayerListBox;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.util.BlockPos;
import net.minecraft.world.World;

public class PowerTest extends BlockContainer 
{

public PowerTest(String unlocalizedName, Material mat) {
	super(Material.iron);
	this.setCreativeTab(CreativeTabs.tabBlock);
	this.setUnlocalizedName(unlocalizedName);
}
public boolean activated = false;

@Override
public TileEntity createNewTileEntity(World worldIn, int meta) 
{
	return new PowerTestTileEntity();
}
public void onNeighborBlockChange(World w, BlockPos pos, IBlockState state, Block nb)
{
	if (!w.isRemote)
        {
		//TODO: If Power is already on then it cannot be turned on again
		if(nb != ModBlocks.pipe)
				{
					System.out.println("Power On");
					if(BlockPipe.isPoweredGlobal == true)
					{
						System.out.println(" We Have Power");
					}
					else if(BlockPipe.isPoweredGlobal == false)
					{
						System.out.println(" We Don't Have Power");
					}
					else
					{
						System.out.println(" Error");
					}
				}
		//TODO Change to Else If Statement to check for errors else then it's an error
				else
				{
					System.out.println("Power off");
				}
        }
}
public boolean pipeNext(World w,int x,int y,int z)
{


	return activated;


}
public void onBlockActivated()
{

}

}

I kow that the stuff im doing in onNeighborBlockChange should be in a method that checks for updates on every tick but it was for testing.

In My Block Pipes i created 2 booleans one that's static, (probably so wrong)

I honestly think  i should be saving this boolean somewhere else but i don't know how/ where.

package com.zombiesurvival.power.pipes;

import net.minecraft.block.Block;
import net.minecraft.block.BlockContainer;
import net.minecraft.block.material.Material;
import net.minecraft.block.state.IBlockState;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.init.Blocks;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.util.BlockPos;
import net.minecraft.util.EnumWorldBlockLayer;
import net.minecraft.world.World;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

public class BlockPipe extends BlockContainer
{
public boolean isPowered;
public static boolean isPoweredGlobal;
public BlockPipe(String unlocalizedName, Material mat) 
{
	super(mat);
	float pixel = 1F/16F;
	//Minx,miny,minz,maxx,maxy,maxz
	this.setBlockBounds(11*pixel/2,11*pixel/2, 11*pixel/2, 1-11*pixel/2, 1-11*pixel/2, 1-11*pixel/2);
	this.setCreativeTab(CreativeTabs.tabBlock);
	this.setUnlocalizedName(unlocalizedName);
}

public int getRenderType()
{
	return -1;
}
public boolean isOpaqueCube()
{
	return false;
}
public boolean renderAsNormalBlock()
{
	return false;
}
public TileEntity createNewTileEntity(World w, int i)
{
	return new TileEntityPipe();
}
@SideOnly(Side.CLIENT)
    public EnumWorldBlockLayer getBlockLayer()
    {
        return EnumWorldBlockLayer.CUTOUT;
    }
public void onNeighborBlockChange(World w, BlockPos pos, IBlockState state, Block nb)
{
	if (!w.isRemote)
        {
		//TODO: If Power is already on then it cannot be turned on again
		if(nb == Blocks.stone)
				{

					isPowered = true;
					if(isPowered = true)
					{

						isPoweredGlobal = true;
						System.out.println("Pipe has Power");
					}


				}
		//TODO Change to Else If Statement to check for errors else then it's an error
				else if (nb != Blocks.stone)
				{

					isPowered = false;
					if(isPowered = false)
					{
						System.out.println("Pipe doesn't have Power ");
						isPoweredGlobal = false;
					}
					else
					{
						//System.out.println("Pipe has Power");
						//isPoweredGlobal = true;
					}
				}
        }
}

}

 

So yeah Thats the code.

 

I know it;s probably all wrong

There is a lot wrong with your code. And not only Minecraft related stuff, overall programming stuff, e.g.:

isPowered = true;
if(isPowered = true)
{...}

There are already 2 things wrong in these lines of code:

• You set

  isPowered

  to

  true

  , then you (try) to check if it is true again (of course it's true, you just set it)
  

• I said you tried to check if it's true, but you actually set it to true, again... Learn the difference between

  =

  and

  ==

  
  

And this is just the beginning...

 

Also, if this is a mod to 'learn' Minecraft modding, don't start with something big, like an energy system. Start with the basics (basic

Block

and

Item

), and then continue. And I doubt you have enough Java knowledge to mod Minecraft, so unless you can proof you know atleast the basics, go learn Java, and then come back to modding Minecraft.