Power Monitor

function populateCells(cellList)
    local periphList = peripherals.getNames()
    cellList = {}
    for i = 1, #periphList do
        if peripheral.getType(periphList[i]) == "energy_cell" then --This might not actually be the name of the peripheral
            cellList.insert(peripheral.wrap(periphList[i]))
        end
    end
    return cellList
end

function queryCells(cellList)
    local power = 0
    for _,v in ipairs(cellList) do
        power = power + v.getEnergyStored() --this might not actually be the right function
    end
    return power
end

function mainLoop()
    local cellList
    populateCells(cellList)
    while true do
        local power = queryCells(cellList)
        --Display things on a monitor
        sleep(5)
    end
end

mainLoop()