By Dave Elliott
Eric Martinot has been one of the key people behind the indispensable annual REN21 Renewable Energy Network publications reviewing the state of play with renewables globally: see The latest one says renewables now supply around 24% of global electricity. Martinot has also taken time out to look in detail at renewable integration issues, and this work has led to some excellent publications, including a useful non-technical overview ‘Grid Integration of Renewable Energy – Flexibility, Innovation, Experience’ for the Annual Review of Environment and Resources 2016 (February 2016). It focusses on the concept of flexibility, which it sees as vital for balancing variable renewables, including small continual changes, sudden large swings in availability, requiring rapid ramp-up of backup plants or other balancing measures, as well as for occasional longer periods of low input.
By Dave Elliott
The vehicle to grid (V2G) debate continues, offering a way to balance variable renewables and also demand peaks, by using the batteries of electric vehicles, linked to the grid when parked at home, to store excess power during low demand periods, ready to export when demand is high and renewables low. It sounds a clever idea but in addition to economic issues (e.g. the extra costs of the home-based power uploading system) it opens up some interesting logistical issues. (more…)
by Dave Elliott
The US is pressing ahead with renewables, with around 60GW of wind and 10GW of PV solar already in place. But that means some system operation issues are coming to the fore. Since these sources vary, as does demand, when there is surplus output from wind of PV, should it be stored or just dumped?