The graph above captures the scope of solving the long term renewable energy intermittency problem with energy storage using California as an example. It shows that wide scale geographic intermittency follows an approximate inverse power rule. Given an intermittency duration in days it predicts the number of such events in a year using the relationship: Number of events = Constant/(duration of event)^2. So say Constant = 10 for California, then the number of 10 day events would be 10/10^2 = 10/100 =0.1 or one event every ten years. The number of two day events would be 2.5 per year. 20 day events would be one every 40 years. 40 day events about every one hundred and sixty years. This profile matches California's history of winter storms. Other geographies will have better or worse profiles but all generally follow the inverse square rule.
Even if storage became ten times as affordable as today, there would still be a reasonable probability of far more than 10 day outage events. Politics does tend to ignore lower probability long term problems, but the counter point is that these long duration events represent significant natural disasters where the electricity supply is crucial to survival.
The graph is only an approximation but the model applies generally to weather related events. Severe events occur infrequently and the more severe the much less frequent. Global warming appears to be increasing the severity of infrequent weather related events, be they storms, floods, droughts, fires, hurricanes, extreme heat, extreme cold etc.
Beyond one day events the amount of storage needed becomes unaffordable at current and foreseeable costs. The alternative solution then becomes additional generation far away outside the region of the intermittency events with long distance transmission to connect this additional generation to California. This is the general solution offered up by academic studies like those from Mark Jacobson at Stanford. The simple problem with these solutions is cost, as more than doubling generation and adding the necessary amount of new long distance transmission would at least triple the cost of California generation alone and the necessary nighttime storage adds another factor taking the total to four times California generation alone. This does not address the political problem of getting states to agree to regional solutions and environmentalists and others who object increasingly to transmission lines, wind farms and large solar arrays.
Everybody is an environmentalist until they are confronted with the cost. If electricity were four or five times its current price, the broad political will is unlikely to last. Clean energy advocates are concerned about the threat of climate change and either don’t care about costs or just wish them away and assume costs will reduce. This will not persuade the broad populace or the developing world where economics are paramount.
By Edmund Kelly
Even if storage became ten times as affordable as today, there would still be a reasonable probability of far more than 10 day outage events. Politics does tend to ignore lower probability long term problems, but the counter point is that these long duration events represent significant natural disasters where the electricity supply is crucial to survival.
The graph is only an approximation but the model applies generally to weather related events. Severe events occur infrequently and the more severe the much less frequent. Global warming appears to be increasing the severity of infrequent weather related events, be they storms, floods, droughts, fires, hurricanes, extreme heat, extreme cold etc.
Beyond one day events the amount of storage needed becomes unaffordable at current and foreseeable costs. The alternative solution then becomes additional generation far away outside the region of the intermittency events with long distance transmission to connect this additional generation to California. This is the general solution offered up by academic studies like those from Mark Jacobson at Stanford. The simple problem with these solutions is cost, as more than doubling generation and adding the necessary amount of new long distance transmission would at least triple the cost of California generation alone and the necessary nighttime storage adds another factor taking the total to four times California generation alone. This does not address the political problem of getting states to agree to regional solutions and environmentalists and others who object increasingly to transmission lines, wind farms and large solar arrays.
Everybody is an environmentalist until they are confronted with the cost. If electricity were four or five times its current price, the broad political will is unlikely to last. Clean energy advocates are concerned about the threat of climate change and either don’t care about costs or just wish them away and assume costs will reduce. This will not persuade the broad populace or the developing world where economics are paramount.
By Edmund Kelly
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