Research Chicago electrical distribution grid impacts from electrification #34
Description
What
When a house switches from gas to all electric appliances, it can cause additional strain on the distribution grid. The homes will also need to buy more physical objects, covered in a separate ticket.
In practice those upgrades are very lumpy (new wires, new transformers) and irregular, but we can approximate them in aggregate with long-run marginal costs (LRMC) per kW. Real distribution grids don't neatly line up with upgrades for city blocks (or individual homes!), but nevertheless LRMC provides a convenient way to get ballpark estimates for either.
Why
Right now we're modeling NPA capital costs by just focusing on the gas pipes and home appliances. However, we should expect that grid upgrades will be triggered from electrification.
The real reason we're doing this modeling is because we want to be able to explain the relative costs of an NPA vs LPP + scattershot electrification. Scattershot electrification has lower upfront capital costs, but larger total capital costs because you are paying for the pipes AND grid upgrades.
How
For each residential unit (home or apartment), we calculate:
Δpower = avg_power_electrified - (pct_ac * avg_power_ac)
upgrade_cost = Δpower * LRMC_kW
That is, the change in peak power draw per residence is going to be the power draw during mid-winter electric heating (and other appliances), minus the average peak power draw during mid-winter. Not all homes have AC, so on average the peak draw is less.
Once we have that change in peak draw, we can get the upgrade cost by multiplying the change in the peak power by the long run marginal cost per kW.
Note that we're assuming here that the LRMC already accounts for usage not being perfectly correlated; that is, we're treating it as a LRMC at the meter, rather than a LRMC at the distribution node. This results in an over-estimate of costs, but simplifies the analysis.
In the future, it might make sense to scale residential units by square footage as well, to account for higher electrification costs for larger units, but since we're not doing that for capital costs that's not necessary at the moment.
Deliverables
- Fill in IL NPA Input data, specifically
- LRMC per kW (low and high estimate)
- Average peak kW summer draw with AC
- Average peak KW winter draw with heat pump + HPHW + stove
- Average sqft for residences in Chicago
- Average headroom (in kW) for residential-focused distribution grid, if available