With an ambitious bill planning a 100% renewable energy use in 2050 pending in the Hawaii legislature, states are looking towards the island for its example. With fossil fuels occupying an 80% of the total energy use, the country still has a long way to go. Yet, the utility company managing the second biggest grid on the island even claims to be able to reach 90% renewable energy use by 2030 with net savings! So what’s their secret? And then what’s the problem?
As for now, Hawaii is relying on immensely expensive oil- and gas imports – the highest rates of the nation because of high shipping costs. In combination with that, the costs of renewable energy have declined dramatically due to technological development and subsidies. So again, what’s the problem? The problem resides with the imminent nature of solar panels and wind turbines. These renewable energy sources produce energy whenever the sun shines or the wind blows – not affected by our command in any way.
The biggest problem of our grids is that production and consumption have to be precisely balanced. We have to produce the exact same amount of kW that we consume at the same time, for the simple reason that energy storage is not economically viable. We cannot store the surplus energy that we produce for later use. This complex balancing-the-energy-grid job resides with the Transmission Net Operator (TNO), an ‘entity’ standing in between producers and consumers, that measures how much is being consumed and regulates energy production accordingly.
So logically, the sole use of wind and solar energy would make the economy completely dependent on the wind and the sun and increase the risk of imbalance of production and consumption – resulting in black-outs or brown-outs. Until they manage to develop the necessary energy-storage technology, they would need a back-up system, providing for the energy shortage when the renewable energy sources don’t provide sufficient energy. This back-up system nowadays is still fossil fuel, since a back-up system of bio-mass energy would also require Hawaii to expensively import bio-waste. Concluding, Hawaii risks becoming too green to function.
Other countries that are introducing green energy are running into similar, yet slightly different issues. Whereas for example the Netherlands has not developed renewable energy use as far that they produce too much to balance it, they have other problems. Traditionally, there was a vertical line running from producers to the transmission and distribution net, towards the consumers. This top-down line, in which the Transmission Net Operators can easily measure consumption and regulate production and thus balance the net, is turned upside down.
Consumption cycles are disrupted and there is a new stream of unregulated production on the grid.
With the promotion of solar panels, heavily reducing a household’s utility bill, we can see a bottom-up development. The law requires the grid operators to grant everyone access to the grid to sell their self-produced energy. This means that hundreds of households have started to use their own energy and send surplus energy back to the grid – completely unregulated. As a result, consumption cycles are disrupted and there is a new stream of unregulated production on the grid. This immensely complicates the TNOs balancing-the-grid job, raising the question if our grid is ready for all this green energy.
So back to Hawaii. A Stanford research team concluded that there were two main solutions. One is to keep fossil fuels as a back-up balancing system, minimizing the use of fossil fuels but ruling out a full 100% renewable energy use. The second one is to count on or invest in the development of sufficient energy storage technology. This would reduce the complexity of balancing the grid and enable Hawaii to reach a full dependence on renewable energy. However, if neither of those options is realised, the islands might just become too green to function.